Pilot's Operating Handbook
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Why Maximum Takeoff Weight: Ultimate Load Factor; .Beyond Book Flying; ...Performance at Density Altitudes, ...Density Altitude and You; ...Revisiting Density Altitude; ...Emergency; ...Newer Seat Restraints; ...Shoulder Harness; Areas of Failure; Aircraft Warners; Aircraft Maintenance Checklist; Functional Flight Check; Make a Fuel Consumption Chart; Lean Your Fuel Mixture; POH vs FOM; Make a FOM for Yourself; New Aircraft Checkout; Release; Terms; Weight and Balance; ...Calculating Weight and Balance; ..Weight; Center of Gravity;...Moment; ...Weight and Balance; Gadgets; ...About Your Aircraft; ...On Checking Out Yourself; Manual E6-B Climb Rate; Pitrch + Power = Performance; ...High Altimeter Setting; ...PTS vs Survival; ...Over Gross Operations; ...Left Turning Forces; ...Weight Watchers; ...Manifold Pressure; ...Flying Beyond Expectations; ...Classifications of Aircraft; ...Classification of Airmen; ...G-Forces as Factors of Horizontal Impact Speed; ...Takeoff Safety; ...
Why Maximum Takeoff Weight
--Structural strength and performance requirements mandate required strength.
--61 knot stall speed caps allowable G.A. light aircraft weight
--Minimum climb requirements for singles is go-around in landing configuration as another gross weight cap.
--The most restrictive of stall speed or climb requirement sets gross weight.
--Structural strength has positive limit load for normal category is 3.8G at maximum weight
--Aircraft must support 2.8 pounds without deformation and another 1.4 pounds ultimate load for every extra pound added.
--Any flight overweight gives up margins of strength, climb and stall.
--Same overweight problem is far more serious in twins.
Ultimate load factor is the limit load factor multiplied by 1.5 to provide an additional measure of safety. While structural damage occurs at the limit load factor, structural failure will not occur until the ultimate load factor is reached.
What does it take to make a good pilot? Is there a perfect pilot? Does it mean going by the book? Those who write the 'book' don't fly. They are Legal Beagles trying to protect asses. They know numbers and write them without feeling.
The 'book' is in the heart. Flying is not in the book; not in the checklist. The true flying 'book' is written each day on each flight. The true flying book is judgment-knowing what to do and when. More importantly, what NOT to do.
A pilot never thinks of flying as taking a chance, taking
risks. The pilot is aware of his total environment. When he's
not aware, he asks for help. Knowing when and where to get help
is the pilot's judgment support system. A good pilot studies
accidents. He learns what can go wrong. You learn from the accident
experience of others two basic things.
-- There are accidents beyond the control of pilots.
--The vast majority are pilot error which is a controllable factor.
What is pilot error? It has very little to do with reflexes. Pilot error is 95% a defect in pilot judgment. The FARs and POH restrictions on performance are always there setting the margins of safety. Every so often a pilot must fly to the shoulder of those margins. This means flying to the edges of altitude and airspeed.
Just as in flying, there is more to weather than numbers; a pilot must have a sense of pattern, knowing when enough is enough. Flying, turning back, getting help are all a part of this sense of pattern.
at Density Altitudes
The POH is not reliable as a source of density altitude aircraft performance. Pilots must consider all the variables with up to 50% safety margin above those of the POH. The POH was accurate only at the moment it was in pre-draft form.
As Density Altitude Increases
---Vy ias decreases as weight decreases
---As density altitude increases the Vy speed decreases
---On reaching 8000 feet your Vy speed has decreases five/eight knots
---As density altitude increases the angle of climb ias increases
---On reaching 8000 feet your ias best angle climb speed has increased four/seven knots
---The absolute ceiling for the aircraft is when these speeds meet
---From an 8000 foot airport your ias climb speed should be five/eight knots slower and POH sea level speed.
---At the wrong airspeed the aircraft most likely will be unable to climb out of ground effect.
---While the landing speeds are always the same the climb speeds are not.
---Taking off and climbing at Vx is an emergency speed in density altitude situations you need cooling.
---Maneuvering at Vy is better than climbing at Vx in density altitude situations
---True airspeed, NOT indicated airspeed determines turn radius
---At density altitudes the true airspeed will be significantly higher and require more room for making a turn
---A 30-degree bank increases drag by 50% and a 45-degree bank increases drag by 100%
---At density altitudes you run out of options of making a 180 unless you are willing to surrender altitude.
---NEVER try to make a density altitude turn at slow speed except when planning altitude loss
---Best plan is to fly over narrow spaces where density altitudes + true airspeeds require more room to turn.
---Landing at 8000 foot density altitude increases your true landing speed 5% faster than indicated.
---Gust factors for landing are added as ˝ ias converted to true
---Regardless of density altitude the only constant in all normal landings is the time of flare to touchdown.
---The distance covered in the flare and ground-roll/stopping distance will be greater at density altitudes.
---Aircraft climb speed is measured in feet per minute.
---Aircraft climb gradient is measures in feet per mile. Charts are based on clime gradient.
---You must know how to use the POH chart for takeoff performance
---Consider Sporty’s Takeoff Performance Computer (Item 2091A)
---At density altitudes you are better off not to use flaps during any takeoff.
---Do not use soft-field procedures and flap settings in density altitude situations having an obstacle.
Density Altitude and You
---You will breath in and out 20,000 times today
---Sea level air is twice as heavy with oxygen as air at 18,000 feet
---Intentional deep or rapid breathing at altitude will not increase the percentage of oxygen
---Rapid and deep breathing at altitude will decrease the percentage of carbon dioxide in your blood
---Supplemental oxygen is the only option
---Vision, especially night vision is extremely sensitive to oxygen levels in the blood
---Best to use supplemental oxygen above 10,000 day time and above 6,000 at night
---We do not notice a lack of oxygen but loss of judgment is a first symptom
---At altitude a sense of doling well is a symptom of hypoxia.
---Hypoxic symptoms are faster breathing, headache, lightheadedness, dizziness, tingling, sense of warmth, sweating, tunnel vision, euphoria, so you die happy.
Revisiting Density Altitude
--Pressure altitude, temperature, relative humidity.
--POH performance charts are based only on DRY air or zero humidity.
--POH performance is based on thrust, power, and lift all of which change for the worse with density altitudes.
--POH charts and graphs figure effects of pressure, temperature but NOT humidity.
–Moist air is always lighter than dry air.
--Engine power is set by the amount of air density it uses.
--Moisture spreads the air molecules and reduces the available air to the engine.
--There are no POH figures for humidity.
--Pressure altitude is found by setting the altimeter to 29.92 in the Kollsman window.
--Temperature is found by reference to the aircraft thermometer.
--High humidity will increase the negative effect of high pressure altitude and high temperature by 10-percent.
–Humidity effects are exponential like G-forces in a bank.
–Humidity ranges from 0 = dry, to 100-percent = wet
–Relative humidity is defined as water vapor present compared to that which could be present.
–Relative humidity is given as a percentage of 100-perecent.
–Rule of Thumb effects:
0 to 50-percent humidity with low temperature and low humidity ADD 200 feet
0 to 50-percent humidity with high temperature and low humidity ADD 1000 feet
50 to 100-percemt humidity with low temperature and high humidity ADD 400 feet
50 to 100-percent humidity with high temperature and high humidity ADD 2000 feet.
--90-degrees F at 100-percent humidity add nearly 1500’ to density altitude.
--100-degrees F at 100-percent humidity add nearly 2000’ to density altitude.
--Multiply the two above numbers by the measured relative humidity percentage for the actual correction.
--Combinations of temperature, density altitude density altitude can be increased over fifty-percent by humidity.
--Safer to use humidity correction added to pressure altitude before entering into performance charts.
--An increase of density altitude over 3000-feet is possible due to high humidity
All POH glide distances should be figured with an additional 1000' cushion to allow for pattern turns. A FAA 50 foot obstacle will increase required landing distance by 120%. In an emergency you must do in one try what it took a skilled pilot several tries to accomplish.
Wings use true airspeed not indicated airspeed to get actual climb rate. Indicated airspeed decreases with altitude while true airspeed increases with altitude. The cruise performance charts is based upon pressure altitude, leaning and gross weight. The greatest variance in POH performance figures will be in fuel consumption. Pilots are well advised to leave a 10% margin of safety from the book figures.
Newer Seat Restraints
--Seat belts are a neglected element of flight preparation.
--Shoulder harness add measurably to the safety of the cockpit.
--Safety factors of restraints are design, materials and use.
--Measures of belt safety; Belt safe at 15g’s for two-thousands of a second + Harness at 25 g’s for two-seconds
--Belts and harness better if as tight as possible.
--Inertial reel harnesses are better than fixed.
--Four point harness + inertial reel are best of all.
--Seat belt that slants is better than when vertical.
--Adding restraints cost $1000 per seat but more expensive air bags are coming.
--Failure of seat or seat attachments is hazard area.
–A seatbelt briefing is required before takeoff and landing
Aircraft are designed to channel impact into structure that will collapse while keeping the cockpit in one piece. The human body can withstand up to 16-Gs if the duration is of the worst impact less than 1/10 of a second. Most aircraft accidents are below these limits. Most serious injuries and fatalities are caused by secondary impact of the victim on the interior cockpit. It is not a bad idea to carry a large pillow. Shoulder harness exists in less than 60% of airplanes and the use of these is less than 75%. Every 5% improvement in use rate will save 20 lives a year. Having the belt and harness made as one would solve the problem.
--Use of the shoulder belt can be expected to reduce major injuries by 88 percent and fatalities by 20 percent as opposed to use of seatbelt alone.
--Shoulder harness has been FAA required since December 12, 1986 in newly built aircraft.
--An improperly installed or worn harness can cause serious injury.
--The belt buckle should be positioned to the side of your hip.
--Dual shoulder harness requires a tie-down strap to keep the seatbelt in place.
---A locked seat is a necessity.
---Retro-fit harness will multiply many times cockpit survivability.
---Safety depends on proper use, construction of belts, design of system.
---Seatbelt only protects you to 15 G’s for 2/1000 of a second.
---Shoulder harness protects you to 45 G’s for 1/tenth second or 25G’s for 2/tenths of a second.
---If you can tighten your belts a bit before impact you greatly improve your chances.
---Inertial reel harness is better than fixed type.
---Four point harness are best at keeping you from bouncing off the cockpit boundaries.
---Five point harness depends on the type of seat involved. Air bags are in planning stage.
---Ceiling mounts reduce chance vertebra compression.
Total brake failure on one side.
How to make a left turn? If failed brake is on the right, where would you land in a left crosswind? Other options
Process for bringing back on line. How to conserve battery. Minimum electrical use.
Reduce power to minimum required for maintaining flight. Have pilot select options.
Disconnected Throttle cable
No power below 2000 rpm possible. How to land? Use magnetos off-on-off-on-off
Is your carburetor designed to maintain a minimum power if throttle is disconnected?
Blocked air intake
Loss of power but pulling C.H. causes increase and taking it off decreases power.
Stuck Carburetor Float
Sudden engine failure. At near full lean mixture engine starts and continues to run. Try it. Worked for me.
Blocked tank vents
Try primer to get fuel to engine. In Cessna use sump strainer to drain sump and restore fuel flow.
First symptom is low or no oil pressure. Check to confirm that loss of oil is the
Selector function check
(Stealthily during preflight set selector to off) Note: Doing this may well cancel the flight if engine continues to run.
(Simulate inability to change tanks) Note: This is a check on pilot's ability to make an alternate route or diversion.
Sudden engine stoppage
(Stealthily during preflight set selector off) Allow student to taxi. Sudden engine failure can be totally disconcerting.
Sputtering and intermittent stoppage
(Stealthily set fuel selector to intermediate position between off and on.)
Lean aggressively during taxi to runup. Do not enrich during runup. Carburetor heat may not (should not) show drop.
In freezing weather just before flight, moisture may have frozen in pitot tube or static air hole. Airspeed indicator will not register during takeoff. Pitot heat should be tested during preflight in cold weather.
During preflight stealthily cover static air hole with tape. Allow takeoff if aircraft has alternate air and operation confirmed. Note effect with and without alternate air on altimeter and airspeed when making changes of altitude. Recently flew aircraft where Alternate Air must have been on for weeks.
Visually check inflation and then confirm with dial type pressure gauge. Incorrect tire pressure is most common cause of unairworthy light aircraft flight. The inconvenience of checking tire pressure as well as getting air is the problem.
Airspeed Indicator Failure on lift off
Fly attitude and power. Return for landing using power and attitude. Been there and done that.
Altimeter not functioning
Knowing height of terrain or landmarks can be valuable aid. Use difference between full power manifold pressure and 30" as estimate of altitude. Use GPS.
Elevator stuck or broken
Use power and trim to control aircraft along with rudder. I gave a DE a checkride in an unfamiliar C-172 in which, after liftoff he could not use yoke. He flew the 30-miles of OAK flying published procedures and vectors to a perfect ILS approach and go-around.
Gradual power reductions. Use of 7700 and 7600.
Get no-gyro vectors from ATC.
Caught on top
Option 1. Fly to airport that is above tops of clouds. Option 2. Vectors towards airport. Above tops slow and configure aircraft so as to be at or slightly below Vso. Reduce power to start descent on South heading. Hope you break out at bases that will allow safe landing. Don't wait until dark or out of fuel.
The entire instrument panel of an airplane comprises a gamut of warning devices. Nearly every instrument has a color code, operating range or other indicator that is designed to warn the pilot about a specific condition.
There are three distinct warnings possible in most situations. First, there is the positive warning as with the stall warner denoting the approach of a stall condition. Second, there is the false positive warning as a stall warner that goes off prematurely. The third, is the false negative warning as when a stall warner does not go off at all. Any aircraft system can fail and warning systems can fail in several different ways. Light bulbs are a common failure point in most warners.
An AC powered warner and gauges will remain stuck where they were when power failed. DC powered warners and gauges will fall to zero. The most noticeable of the gauges doing this is the fuel gauge. The memory device for this is, "AC lies; DC dies." Optical sensors can be fooled as well as affected by their location. A pilot should know where the sensors are, their mode of operation and the way to check for a false positive indication i.e. a failure indication where no failure exists. I once took off from a mountain airport and at the far end of the runway my cockpit was filled with smoke. Someone was burning trash but it made for some exciting moments.
I recently had a false positive when I happened to notice that the carbon monoxide button had turned blue. This is certainly a cause for concern so we ventilated the cabin. On the ground we were unable to duplicate the problem. We contacted the manufacturer and found that in a tightly closed cockpit with sufficient people aboard it is possible for the CO indicator to give a false positive indication. Something to know and think about.
Partial panel training should include not just the use of warning flags on such instruments as the turn coordinator and attitude indicator, the pilot should know what other instruments will provide a check for failure or false indication. The vacuum gauge that does not read until power is advanced is telling you that a failure exists in the near future. The noise from a gyro instrument is a warning to be heeded. If the attitude indicator does not quickly stabilize when recovering from turns or maneuvers, it is telling you that is will likely fail when you most need it when in turbulent IFR conditions. Contrary to common opinion, the stall warner is not an airspeed sensor; the stall warner is an angle of attack sensor. It will activate at any airspeed slightly before the angle of attack reaches the stall. The failure of a warner of any kind to work means that it will give no signal to the pilot. This is a false negative. The relatively common situation in well-used aircraft is to find that the key can be removed from the magneto switch from any setting. The warning that exists here is that maintenance should be informed and the situation corrected immediately.
Thus we have on our aircraft various warnings that may or may not occur when appropriate conditions exist. Where circuit-breakers can be pulled to disable warning systems we add the human element. All too often the damage occurs when someone fails to reset the breaker. Any indicator, such as flap or gear, should be visually verified. The first time you fail to verify will likely be the time you should have.
A pilot must be aware of the small warnings that exist in aircraft operations. Tires that are 'cupped' on the sides are indicative that landings were made when side loads and braking occurred simultaneously. Perhaps a refresher lesson in crosswind landings would help. When the bearing noises of the attitude indicator become obvious you have a failure waiting in the wings. The same applies to a zero vacuum reading at idle. Clicking and clacking in the nose wheel will ultimately lead to damaged engine mounts. Failure of seats to move smoothly is a warning that something is wrong with the rails or the slides. Being unable to exit an aircraft quickly can be hazardous to your health. A magneto switch that allows a key to be removed in other than the 'off' position means that a negligent or poorly checked out pilot can leave the aircraft waiting with a 'hot magneto' for the next person to fly. The pilot who fails to put in the control lock is subjecting the aircraft to potential damage should the winds become gusty. Maintenance costs money, no maintenance costs lives. Pilots who are given checkouts casually without attention to proper care and treatment will regard the aircraft as a 'rental' and behave accordingly. Truly caring pilots will take care of airplanes, even rentals.
No flight must be flown if the pilot sees risk ahead that is beyond his and/or the aircraft's capability. Preparation alone will not prevent a hazardous occurrence. Good pilots avoid complacency and acquire knowledge that does not exist in the POH.
--Spinner and back-plate to cracks or looseness
--Blades for nicks and cracks
--Hub for grease or oil leaks
--Bolts for security and safety wire
Engine Run-up check
--Magneto drop and grounding
--Mixture and throttle for smoothness of operation
--Propeller control for smoothness of operation
--Engine idle with C.H. on
--Carburetor heat and alternate air
--Alternator output under load
--Vacuum system readings idle to power
--Fuel pressure if applicable
--Fuel selector in all positions
Engine Compartment Check
--Remove cowling; clean and check fasteners and condition
--Engine oil for quantity and condition. Change filter and oil; check screen
--Check oil temperature sensor for leaks, security and fittings
--Check oil cooler for condition, security, leaks
--Remove plugs, clean and gap, replace top to bottom and bottom to top, torque to specs
--Check mags for security, cracks, wiring and insulation
--Check harness for chafing, cracks, cleanliness
--Check cylinders for security, cracks, fins
--Check rocker box for security and leaks
--Remove air filter and clean by tapping, replace
--Check all air inlets for leaks or holes
--Check intake clamps and seals for leaks, stains
--Check priming lines, clamps and fittings for stains, leaks, security
--Check exhaust stacks, connections, clamps, gaskets, muffler and heat box for cracks, leaks
--Check fuel line condition for stains, leaks and security
--Drain one pint of fuel from each sump and check for contamination
--Check vacuum pump and lines for condition and security
--Check crankcase and breather tubes and clamps for condition and security
--Check engine mounts for condition, security, and cracks
--Check engine baffles for condition, security and placement
--Check wiring for chafing, cracks, insulation and condition
--Check firewall and firewall seals
--Check belts for condition, fraying, and tension
--Check starter and alternator for condition , safety wire, and security
--Check brakes, lines, and fluid for level, leaks and condition
--Lubricate engine controls
--Check 'door' operation of alternate air and carburetor heat
--Check doors for condition, fit, latches and hinges
--Check upholstery and interior panels
--Check seats, belts and operation
--Check Trim movement indicator and exterior tab
--Check rudder pedals and brakes for balanced operation and security
--Check operation of parking brake
--Check controls for smoothness, security, and freedom
--Check lights and beacons
--Check heater, defroster and air vents ducts for condition, operation and security
--Check windshield and windows for cleanliness, condition, leaks, and crazing
--Check instruments and lines for operation and security
Fuselage and empennage Check
--Check baggage door condition and operation
--Check battery for water, corrosion and condition
--Check antenna mounts and wiring for corrosion, condition and security
--Check hydraulic lines and connections for leaks, security and fluid.
--Check ELT for date/use compliance, switch position and operation
--Check all control surfaces, hinges, linkage, cables and weights for operation and condition
--Check all control surfaces for lubrication
--Check static ports
--Check wing tips for cracks and security
--Check position lights and strobes for security and operation
--Check flaps for lubrication. operation and security
--Check balance weights for condition and security
--Check fuel tanks, vents, indicators and caps for condition, operation and placards
--Check pitot and static port for security and condition
Landing Gear Check
--Check strut extension
--Check scissors and shimmy damper for leaks and security
--Check wheels and tires for defects, pressure, security
--Check hydraulic lines and connections for leaks and security
--Check Gear structure for condition and security
--Check retracting mechanism, doors, switches, and condition
--Check brakes, pads, lines for wear, security and leaks
Functional Flight Check
--Brakes before and during taxi
--Engine and propeller for power and smoothness during run-up
--Engine instruments for 'in the green'
--Power during takeoff
--Electrical system under load
--All avionics and VOR Check
--Heater, defroster, ventilation
a Chart of Fuel Consumption
Since the first day we bought the airplane we have maintained a fuel/time log for our aircraft. This procedure should be mandatory. Even so there are errors. Not all 'top-offs' are the same. This was amply shown when for one flight we recorded fuel consumption of 7.7 gallons per hour. This indicated that the ramp position would not permit a complete fill up or the line boy quit too soon.
Still, we have several hundred hours of recorded fuel consumption running in the high eights. By planning for nine gph we can plan our time of flight from our time in fuel. Throw out unusually high or low figures that seem out of the normal range. You can compare fuel consumption figures with you POH and with consumption rates for horsepower of the engine. Safe flight time will be 75% of your confirmed rate of consumption. Your consumption charts should be figured for at least three different weights based on single pilot, both front seats and gross weight. Run your fuel rates accordingly.
Use your 75% of fuel time for planning your trip lengths.
If you wish you could vary your range once aloft and encountering
actual winds. Considerable range differential is possible in
a C-172 where ground speed can easily vary from 90 kts to 120
kts. Over a three-hour flight the range difference is 90 miles
or more. On a flight over the west, east of California, this
90 mile difference means that your best refueling choice will
be at 2.5 hours instead of 3 hours simply because you will be
into reserves because of the distance between airports. Once
you decide to fly into your reserves you have stopped being the
safest pilot you can be.
Learn to read your gauges. Even when full, a gauge may not indicate full. Some tanks seem to feed faster than others. Some gauges vary in the speed of movement from different levels. Watch out for the gauges that decide to drop all at once. Accuracy is required by FAR only when empty. If you intend to crowd your fuel limits get a digital totalizer.
Your Fuel Mixture
0. If you are leaned for run-up, pulling the carburetor heat may not get you an rpm drop.
1. When taxiing, lean to the point of engine failure. This will cause the engine to stop if you forget to enrich for takeoff.
2. To attain better aircraft performance and reduced fuel consumption.
3. To prevent sparkplug fouling and smoother engine operation.
4. To reduce engine maintenance.
5. For high-density landings and takeoff
The method and extent you should lean an engine depends on
the engine manufacturer's recommendation and the fuel used. Leaning
is not a precise adjustment. Most operators tend to fly a bit
on the rich side since being overly lean can damage the engine at higher power
Without an exhaust temperature gauge you would lean by turning
the mixture counter-clockwise until able to detect a 'roughness'
in the engines performance. Then you enrich by turning the mixture
clockwise until the engine smoothes out. At 75% power aggressive
leaning will not harm the engine and will raise the internal
operating temperatures high enough to prevent internal fouling.
The exhaust gas temperature gauge allows you to lean gradually while watching a needle more up a graduated dial with 25-degree divisions. You should continue to slowly lean until the needle stops climbing. Once it starts back down it is telling you that the engine has gone past its maximum power point for that altitude and power situation. Now you reverse the process and enrich the mixture by turning the knob to the right. You take the needle past its peak until it has dropped two marks or 50-degrees below peak. Any change in power or density altitude will require a repeat of the process.
With the advent of 100LL octane fuel being used in engines designed for 80/87 octane fuel the engine manufacturers have recommended leaning for taxi and even leaving it leaned during run-up. It is the lower spark plugs that tend to accumulate lead or other deposits in the gap of the plugs or on the valve stems. This comes from incomplete combustion of fuel and fuel that keeps the engine too cool for efficient operation. Aggressive leaning is needed for aircraft that use the Lycoming 235 (C-152 and Beech Skipper) to allow the internal heat to vaporize any condensation and residue accumulations. A leaned engine will let you know immediately on takeoff should you forget to go rich on takeoff.
One unintended consequence of doing your run-up with a well-leaned engine is that the application of carburetor heat will not produce the usual drop in RPM. The typical response and mine in the first instance is that the C.H. is inoperative. A slightly richer mixture will produce the normal RPM drop. I now make it a practice not to go full rich until actually taking the runway.
Should your magneto check indicate a fouled plug on one magneto or the other, the burn-off procedure consists of going to 'both' and increasing the power to above 2000 RPM. This higher power will, hopefully, raise the internal engine temperature sufficient to vaporize any accumulation of residue in the cylinders, valves and spark plugs. Then you check for proper power on each magneto. If one remains rough, you try to get maximum heat and power on just one magneto. This does not always work and the engine should be seen by a mechanic.
Any takeoff at a high-density altitude airport should be preceded
by a full power run-up and leaning for best power. This should
be performed as efficiently as possible. I usually add a bit
of 'rich' to prevent detonation.
Having once experienced an engine failure on the runway at Flagstaff, AZ because of a full rich mixture, I now check my mixture setting at pattern altitude and use that for landing while being sensitive to smooth engine operation during a go-around. One of the best ways to become acutely aware of the benefits of proper leaning is to fly the Rockies in a C-150 or a loaded C-172. Engine temperature is the clue to separate the two causes of engine roughness, too lean or too rich.
POH vs AFM
The POH is generic manufacturers publication that covers a given type and model of an aircraft. The POH cannot be used instead of a required AFM. Both the POH and AFM will have the operating limitation and required markings and placards for the aircraft. The difference in the books is that the AFM is specific to the aircraft. The AFM can be substituted for the POH but the POH cannot substitute for the AFM.
Make a FOM for Yourself
If the general aviation pilot would only make printed pre-decisions of what he is going to do in a variety of the emergency situations, much of the statistically advantages that airlines have over general aviation would be eliminated. As an aircraft owner, we should have a FOM or flight operations manual, which prescribes actions to be taken. Preliminary to the development of the FOM would be developing an aircraft performance chart for various operational weights.
Checklists alone are inadequate. The owner pilot or even the renter pilot of the same aircraft can make a performance chart for takeoff, cruise, and landing, which will cover parameters for wind directions and velocity. Make a chart of performance call-outs and altitudes all of which constitute pre-decisions for the situation. Consider a call-out for gear retraction on takeoff. Another call-out for minimum return to the runway is desirable. Such a chart would be a part of the pre-departure procedure review. The margin of safety differential is not so great between the two major areas of flying that it could be erased by such a simple program/procedure based upon just pre-deciding what you are going to do.
The airlines have very specific limits that set their ability to shoot an approach. The usually forgo the making of non-precision circling approaches at night. They have numerous continuous altitude call-outs and crosswind limits. Perhaps every pilot should have such a list based upon a derived set of criteria such as recency, proficiency, and experience.
1. Qualified and current Instructor
2. Manufacturer's training course
3. Study POH and AFM
Weight and Balance
Equipment list (unique equipment)
Ground and Flight Checkout
Useable fuel, burn rate, system operation, selectors, gauges, leaning procedure
Normal indications of oil pressure, temperature, volt/amp readings, RPM
Limitations on performance, weight and balance and V speeds
Gear, electronics, hydraulics, electric
Abnormal indications of all instruments (Type flight simulator)
Aircraft papers and logbooks
Vso, Vsl, Vr,1,3 Vso, Vx, Vy, Vlo, Vle, Vfe, Va, Vne, L/Dmax
Airspeed indicator speeds, placarded speeds, FOM speeds
Blindfolded cockpit check
1. Detailed preflight
2. Pre-start, start, taxi, runup, pre-takeoff
3. Takeoff series and aborted takeoff
4. Four basics in cruise and slow cruise
5. Slow flight and minimum controllable
6. Stall series
7. Steep turns
8. Emergency simulations
9. landing series with go-arounds
10. Shutdown, post-flight, tiedown
11. Fueling procedures and records
12. Detecting discrepancies
1. Pilot Certificate
2. Medical Certificate
3. Flight review or in lieu of endorsement
4. Flight recency of 61.57
1. 3-landings day within 90-days
2. 3-landings to full stop within 90-days
3. 6-approaches with holding and navigation for IFR currency
Part 91 Requirements
1. Annual inspection
2. 100-hour inspections
3. Airworthiness directives (ADs)
4. 24-month altimeter and encoder inspection and tests
5. 24-month transponder inspection and test
6. 12-month ELT inspection and battery test
7.30-day VOR operational check.
RRadio station license (required out of U.S.)
OOperatring limitations in POH or AFM or AOM
WWeight and balance papers
This is a 'release' I obtained from a pilot many years ago.
ras Group opinion not worth the paper it's written on.
Passenger has requested that he or she be allowed to ride as a guest in the above identified aircraft with full knowledge and understanding that the owner and operator may not maintain any insurance coverage of any kind with respect to the aircraft or the operation thereof and that the aircraft is not necessarily certified by the Federal Aviation Administrator or any other agency or body for passenger transport and is inherently dangerous. Operator and owner make no representation or warranty of any kind as to the airworthiness or other condition of the aircraft or the authority, experience, or qualifications of the pilot. Passenger undertakes passage in the aircraft voluntarily at his or her sole risk without any inducement whatsoever.
Therefore, passenger, for himself or herself and for his or heirs, administrators, executors, successors and assigns, hereby forever acquits, quitclaims, releases and discharged owner and operation and his respective heirs, harmless from and against, any and all claims, demands, debt, expenses, costs, damages, liabilities, actions, and causes of law or in equity, whether with respect to person or to property and in any way arising, directly or indirectly, out of or from passenger's gratuitous passage in the aircraft.
Passenger certifies that he or she is over the age of 21 years
and fully understands the risks involved in this matter and the
ompleteness of the release intended hereby.
Signed by passenger
Since 80% of aircraft accidents (Probably fatalities as well) are attributed to pilot error, the above is worthless because you cannot be excused from liability due to pilot error.
ADF Automatic Direction Finder
ADIZ Air Defense Identification Zone
AFB Air Force Base
A/FD Airport/Facility Directory
AGL Above ground Level
AIM Aeronautical Information Manual
AIRMET Airmen's Meteorological Information
ATC AIR Traffic Control
ALS Approach Lighting System
AMEL Airplane Multiengine, Land
ARTCC Air Route Traffic Control Center
ASEL Airplane Single Engine, Land
ASOS Automated surface Observation System
ASR Airport Surveillance Radar
ATIS automatic Terminal Information Service
ATP Airline Transport Pilot
AWOS automated Weather Observation System
CAS Calibrated Air Speed
CAT Clear Air Turbulence
CFI Certificated Flight Instructor
CG Center of Gravity
CT Control Tower
CTAF Common Traffic Advisory Frequency
DF Direction Finder
DH Decision Height
DME Distance Measuring Equipment
DP Departure Procedure (Replaces SID)
DVFR Defense visual Flight Rules
EFAS En Route flight advisory Service
EFC Expect Further Clearance
ELT Emergency Locator Transmitter
ETA Estimated Time of Arrival
ETA Estimated Time en route
FAA Federal Aviation Administration
FAF Final Approach Fix
FBO Fixed-Base Operator
FDC Flight Data Center
FL Flight Level
FSDO Flight Standards District Office
FSS Flight Service Station
GADO general Aviation District Office
GPS Global Positioning System
GS Glide Slope
HAA Height Above Airport
HAT Height Above Touchdown
HIRL High Intensity Runway Lighting
HIWAS Hazardous In-flight Weather Advisory Service
HIS Horizontal Situation Indicator
IAF Initial Approach Fix
IAP Instrument Approach Procedure
IAS Indicated Air speed
ICAO International Civil Aviation Organization
IFR Instrument Flight Rules
ILS Instrument Landing System
IM Inner Marker (Obsolete)
IMC Instrument Meteorological Conditions
KIAS Knots Indicated Air Speed
KTAS Knots True Air Speed
LAA Local Airport Advisory
LAHSO Land and Hold Short Operations
LDA Localizer Type Directional Aid
LMM Locator Middle Marker
LOM Locator Outer Marker
MAA Maximum Authorized Altitude
MALS Medium-intensity Approach Light System
MAP Missed Approach Point
MC Magnetic Course
MCA Minimum crossing Altitude
MDA Minimum Descent Altitude
MEA Minimum En Route Altitude
MEI Multiengine Instructor
MHA Minimum Holding Altitude
MM Middle Marker
MOA Military Operations area
MOCA Minimum Obstruction Clearance Altitude
MRA Minimum Reception Altitude
MSA Minimum Safe Altitude
MSL Mean Sea Level
MTR Military Training Route
MVA Minimum Vectoring Altitude
NAS National Airspace System
NAS Naval Air Station
Navaid Navigation Aid
NDB Nondirectional Radio Beacon
NFDC National Flight Data Center
NORDO No Radio
Notam Notice to airmen
ODALS Omnidirectional Approach Lighting System
OM Outer Marker
PAPI Precision Approach Path Indicator
PAR Precision Approach Radar
Patwas Pilot's Automatic Telephone Weather answering service
PIC Pilot in Command
PIREP Pilot Weather Report
POH Pilot's Operating Handbook
PT Procedure Turn
PTS Practical test Standards
PTT Push to Talk
RADAR Radio Detection and Ranging
RAIL Runway Alignment Indicator Lights
RAREPRadar Weather Report
RCLM Runway Centerline Marking
RCLS Runway Centerline Light System
RCO Remote Communications Outlet
REIL Runway End Identifier Lights
RMI Radio Magnetic Indicator
RVR Runway Visual Range
RVV Runway Visual Value
SAR Search and Rescue
SDF Simplified directional Facility
SIC Second in Command
SIGMET Significant Meteorological Information
STAR Standard Terminal Arrival Route
STOL Short Takeoff and Landing
SVFR Special Visual flight Rules
TACAN Tactical Air Navigation Aid (Military VOR)
TAS True Airspeed
TC True Course
TCH Threshold Crossing Height
TDZE Touchdown Zone Elevation
TDZL Touchdown Zone Lights
TEC Tower En route control
TIBS Telephone Information Briefing Service
TPA Traffic Pattern Altitude
TRSA Terminal Radar Service Area (Black outline)
TWEB Transcribed Weather Broadcast
UNICOM Universal communication Frequency
UTC Universal Time Coordinated
VASI Visual Approach Slope Indicator
VDP Visual Descent Point
VFR Visual flight Rules
VHF Very High Frequency
VMC Visual Meteorological Conditions
VOR VHF Omni Range
VOR-DME VHF Omni Range with Distance Measuring Equipment
VORTAC VOR and TACAN combined
VTOL Vertical Takeoff and Landing
WCA Wind Correction Angle
Gross weight is the sum of aircraft empty weight plus the load of pilot crew, passengers, baggage and fuel. More importantly is that the total weight be located inside the center of gravity range. Being over weight alone means that the climb performance will be reduced. The aircraft has never been tested outside of the center of gravity range. Measurements are often made within .1 of an inch to set the center of gravity range.
A loading that is less than one inch beyond the aft C.G. range
line does a number of things to the aircraft performance
--The further aft the C.G. the lighter to the touch are the control forces.
--You will have excessive aircraft reaction to small elevator movement.
--You could unknowingly exceed the design limits of the aircraft.
--The plane will be unstable in pitch.
--Trimming for stable flight will be difficult.
--When you slow up the aircraft will go even slower.
--When you go faster the aircraft will go even faster
--Increased tendency to stall and enter a stall spin.
--Inability to be as effective in stall or spin recovery.
---CG is between 20 and 25% of wing’s chord
---Safety of CG is relative to aft and forward CG limit in POH
---Prime factors are center of lift, center of gravity and elevator authority.
---Principle numbers are gross weight and CG range that must be within envelope
---Weight and balance is inherent to the design based on standard temperature at sea level
---Most aircraft are not designed for extreme altitudes or temperatures.
---Fuel use tends to shift CG towards the rear.
---Being outside the CG range is more serious than being over weight
---Being forward of the CG limit means that elevator authority will be less at low speeds.
---Forward of CG limits causes slow speed landings to hit the nose wheel, spins are very dangerous.
---Being aft of the CG limit means that elevator authority will be exaggerated and very sensitive.
---Landing flare will be excessively nose high and a stall may not be recoverable.
---An aft CG loading may result in an unrecoverable flat spin.
---Being over gross affects all performance figures.
A loading that is less than one inch forward of the forward C.G. range line will cause:
--Inability to raise the nose during low speed flare.
--Inability to raise the nose at a normal lift off speed.
Calculating Weight and Center of Gravity
--All figures must be attested to by an A & P.
--A new weight and balance sheet must be completed, dated and signed off by an AI.
--Weight is measured using at least three properly calibrated scales.
--Tie controls to neutral in a wind free space.
--Empty cockpit areas of loose items
--Weigh chocks before using on scales and subtract this weight from the sum weight of all scales.
--Sometimes the manufacturer uses a 'fleet' weight average for all of a series of aircraft.
--Some aircraft have never been actually weighed or re-weighed since manufacture.
--Read scales and add to get sum.
--Subtract the fuel (weight x arm) moment to get the basic moment.
--Aircraft must be level in pitch and roll axes. (Longitudinal and lateral)
--Raise level aircraft to normal extension of struts.
--Measure the arms from the datum of the aircraft to the center of the wheel axles with 1/10 inch.
--Use a plumb bob to locate axle centers.
--Fuel use may shift the C.G. so worst-case figures must be computed.
--Multiply the arm by the wheel weight to obtain the moment.
--Nose wheel moment will likely be negative.
The term moment is used in physics and engineering) to describe a rotational motion. Vectors are a cross product of a force and some kind of lever arm.. The word comes from a Latin root meaning. to move.
Weight and Balance
--Leveled aircraft is weighted for empty weight and empty weight and empty-weight center of gravity
--Data must be signed and dated by A & P on aircraft papers.
--Current equipment list is required
--Track dates and hours-in-service by including part number and serial number of every installation.
--Good time to get this information is during annual. Continue as replacements occur.
--Run a comparison between what was original and as it exists equipment.
--Intent is to list everything that exists on the aircraft.
--A certified copy of the original equipment list can be obtained from the manufacturer.
--Aircraft from the mid-seventies will find the POH a valuable source of original equipment data.
--Factory lists have weight and balance data for every item installed on the aircraft.
----STC installers have data on weight and balance effects.
--Make a spreadsheet for complete record keeping of all equipment
--Weight and balance is valid only when verified with the equipment list.
--Timer with huge display and 3 separate timers that can be preset for
things like 1 minute countdowns (flashing light when time is up).
--Subscription to Flight Training magazine and this newsgroup.
--GOJO citrus hand cleaner wipes.
---My nylon tri-fold kneeboard in combination with the kneeboard-layout airport information sheets from AOPA website.
---My Serengeti sunglasses.
---Dual countdown/count up timer. Pay $24.00 for it at an aviation supply
place or half that at your local Wal-Mart.
--Mobile phone - useful for calling the fuel truck without having to hike back to the FBO, getting the ATIS without starting up the engine or draining the battery, filing flight plans, *closing* flight plans when you suddenly remember 15 minutes after driving away from the airport :^)
--Watch - don't bother with a fancy aviation watch. Mine has three key features: analog display, rotating bezel, and a small digital display. Use the rotating bezel to mark departure time when taking the runway - much easier than fumbling with a pencil. The digital display on mine has a second clock (which I keep set to zulu time) and a second stopwatch. If you fly low-wings, an analog watch helps you use the "minute hand" fuel management method (if the minute hand is in the right half of the display, draw from the right tank, otherwise draw from the left).
--Clip on flashlight. Pick up red cellophane from a hardware store or auto parts store.
--I'll second the suggestion for clear-plastic page-holders. I use 8.5"x11", though.
--In the "not really a gadget but I'll mention it anyway" category -internet connection, to get charts from aeroplanner and AOPA
--In the "not really a gadget but I'll plug 'em anyway" category - AOPA membership.
--Fuel sampler. These are always disappearing from rental airplanes.
--I find having the flashlight that clicks from red to white really helpful
-- Jeppesen chart organizer (a spiral bound set of transparent pockets, great for collecting all of the approach charts necessary for a big flight).
--Navaire blackout light (the ones that attach directly to your headset). Awesome product.
--Yoke clip (for attaching approach charts to the yoke)
--Light pen. Has colored light for use at night without damaging night vision.
About Your Aircraft
--What is the maximum oil level at which the engine may be operated?
--Suppose you're definitely above the minimum oil level but there's enough room to add a quart and remain just below max. Should you add that quart? (I already knew the answer for the Cessna 152, but had forgotten where I had seen it. Must have spent 10 - 15 min hunting through the POH.)
--What instruments (flight and engine) continue to work after total electrical failure?
--What flight instruments are unaffected by engine failure?
--Can your radio tune to 122.725 MHz? 122.975? How is it done?
--Where are the antennas for the various units in the radio stack?
--Can you jump-start this airplane from a car?
--Is there a receptacle to connect external electrical power? Where it is? Does the POH have an external power procedure?
--What aspect of a C-182 oil dipstick is a major cause of overfilling with oil?
--A new engine, new interior and a paint job combined with a Flight Management System puts any aircraft into a new regime
Checking Out Yourself
I may have missed something in this thread but I get a sense that some are beginning to confuse safety and legality. Just as in law the person who is his own lawyer has a fool for a client, so does the pilot who checks himself out in an aircraft have a fool for his instructor.
The unrealized differences between the C-172 and the C-150s will be the ones that kill. The engineering differences between the C-150 and the C-152 are significant, as are the changes in different models of C-172s. Those who present their arguments out of ignorance are a danger to themselves and others who might believe dangerous information.
Aircraft manufacturers have a subtle method of ignoring operational
peculiarities that may make their aircraft hazardous for the
uninitiated. Subtle in that there is no mention or acknowledgement
that the situation exists.in the POH. Cessna fuel tanks feed unevenly, Piper has a cabin
support just above the brakes, Beech fuel pump
is not used for landings and some of their engine controls are
different from all others and on and on and on.
There is an eighteen mph difference in Vx for differing models of C-150s. C-172 differ widely in their flap operation and power. There are operational differences in the Hershey-bar and taper wings of the Pipers to say nothing of the length and authority of the stabilator.
E6-B Climb Rate
--You are making a proportion
--Put 60 minutes index under your ground speed
--Read minute time scale as required feet per mile
--Read directly above feet per mine required clime rate as feet per minute
+ Power = Performance
There are five basic flight combinations of P + P = P
1. The best angle of climb pitch gives best angle of climb with full power.
2. The best rate of climb pitch gives the best rate of climb with full power.
3. Liftoff pitch angle with climb power gives a cruise climb at or below 500fpm. Reduced power gives low cruise as used in traffic patterns. At idle gives a minimum-sink descent.
4. Cruise pitch angle with 75-percent power setting gives normal cruise. Low power setting gives approach speed in flap configurations. Without power it gives best glide speed.
5. Descent pitch with cruise power gives cruise descent at 500 fpm or less at high speed. With power off and full flaps is used in landings.
High Altimeter Setting
FAR 91.144 prohibits flight when pressure exceeds 31 inches. The problem is avoided by a NOTAM being issued stating how aircraft will cope with the problem by flying at higher altitudes than charts should indicate.
PTS vs Survival
--Emphasize solving unexpected outside situations and conditions
--Emphasize awareness of distraction and anxiety.
--Expose student to a wide variety of situations to build experience.
--Cover the instrument panel to force recognition of sounds and attitudes.
Over Gross Operation Effects--
--Higher takeoff speed required
--Longer takeoff run
--Reduced rate and angle of climb
--Lower maximum altitude
--Lower cruise speed
--Higher stalling speed
--Higher landing speed
--Longer rollout on landing
--Not as bad as being out of Center of Gravity range.
--Newton's law that there is a reaction to every action
--Rotation of propeller tends to roll/bank aircraft in the opposite direction.
--Left wing is designed to give more lift at cruise to resist torque but causes left yaw.
--Offset of rudder or engine usually the structural fix by manufacturer
--At low-speed and high power these fixes are inadequate so right aileron and right rudder is required.
--In high-speed low power dive these fixes cause right rolling effect.
--Nose above the horizon increases the pitch of the descending blade of the propeller.
--Increased pitch angle causes pull (yaw) to the left.
--To counter both torque and yaw requires use of aileron and rudder.
--P-factor most apparent on tailwheel aircraft takeoff.
--The propeller acts as a gyroscope when force is applied to the propeller disk".
--This force is at right angles to the rotation direction and in the same direction of force applied.
--The rate of the force application determines the precession force that results.
--Familiarity can breed a total indifference to aircraft weight and balance.
--Aircraft center of gravity relates only to the longitudinal axis.
--It is possible to overload an aircraft and still be within the permissible balance range.
--It is possible to under-load an aircraft and be outside the permissible balance range.
--Excessive weight affects every flight performance aspect of an aircraft.
--Given a choice between weight and center of gravity range, take a proper CG.
--The center of gravity range is based upon the ability of the elevator authority to exist at minimum airspeeds.
--Air worthiness standards require controllability throughout the entire flight envelope for certification.
--Flying with rpm/manifold pressure 'squared' is not very efficient,
--Flying squared is safe and conservative engine operation..
--Flying squared is not always the right or best way to operate an aircraft enginje.
--Always obey POH engine limitations and restrictions.
--Select rpm/manifold pressures that work best for smoothness and quiet operation.
--Generally the lower the rpm setting the better for the engine
--Less wear and tear
--Less power is lost due to friction
--Friction can take 5% of engine power at high rpms.
--Lower EGT reduces thermal exposure of engine parts.
Flying Beyond Expectations
Pilots are special in that they soon adopt strongly held opinions because flyers must be totally and absolutely right about what they do while flying. Pilots usually fly as they were first taught. Instructors perpetuate their instruction through their training of other instructors. Only a fraction of the totality of instruction passes through. The problem lies in the apparent selectivity of potentially dangerous practices. As with most behavior, the bad habits seem to develop a life of their own most likely because of instinctive associations.
The more experienced pilot has a standard operating procedure (SOP) that sets a sequence for the complex operations required in flying. The even more experienced pilot has the flexibility required to adapt, ignore, and adjust these standards when necessary. A good example to explain these differences would be a situation was the airspeed indicator sticks or becomes erratic. The pilot who knows his power settings, trim position and flap requirements can easily and quickly make the adjustments needed. A non-airspeed indicator landing should be a part of every student’s training.
Every aircraft and situation has performance capabilities and performance requirements that must be matched. The capable pilot initially applies a standard operating procedure and then flexes as required where a mismatch exists. Instruction should be designed to deliver a student through the limitations of a standard operating procedure into the comfort area of applied flexibility. Applied flexibility means that the pilot will do what it takes to resolve a situation. This is where simulators usually step in, but not necessarily. Creative instruction
can cover the airspeed indicator with a large post-it so only the right seat occupant can read it. The heading indicator can be covered or miss-set.
What we are trying to get is a pilot who can think outside the box created by SOP. What may work is something never mentioned in the POH. You need to have a personal copy of the POH to which you have appended to it all the appropriate writing by pilot-authors, and oral history gleamed at airports. Try the internet and eBay as well. Engine operation as given in the POH does not always give numbers that are best for the airplane or the user. The dearth of adequate information is mostly a legal ploy with little regard for the aircraft user. It behooves the pilot to go outside the available materials to discover everything possible about the aircraft especially in the slowest flight regions. When a crisis occurs what you have learned may save lives yours included.
Classifications of Aircraft
An aircraft is classified when it is certified and approved.
--Set by intended use and limits on operation
--Commuter 19 seats over 19 K pounds/systems
--Restricted with special purpose or limits
--Limited – ex-military
--Provisional new designs
--Experimental research and development
–Determined by type of propulsion
–Determined by similarity of design
Classifications of Airmen
An airman is classified when receiving a certification or license
--Operational characteristics determines class
--Specific make and models of aircraft determines type.
--Class is operational characteristics
--Type is specific make and model.
Category Class Type
Single-engine land Pa-28
Multi-engine land Citation
Single-engine sea DC-3
--Lighter than air
factors of Horizontal Impact Speed
Knots G’s stopped in 20’ G’s stopped in 40’
20 1 <1
40 3.5 2
60 8 4
80 14 7
100 20 10
General rule seems to be the slower you go and the further you slide the
better off you will be.
---Take 150% of POH performance figures to obtain ‘real world performance.
---You calculate performance when you are outside your normal operations
---Takeoff data are weight, altitude, temperature, useful runway, obstacles and distance from end of runway.
---Determine an abort point that requires lift-off at halfway point of runway.
Pop-off ground into crab
.Return to whittsflying
Continued on Page 3.23 About Aircraft Speeds