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About those people who write aircraft POH’s

January 6, 2012

3 words for the people at the big factories who write aircraft Pilot’s Operating Handbooks (POHs):

“GET A MAULE”.

Seriously, a 352 page POH (manual) for a Cessna 172? The manual for a Maule M7 is about 40 pages or so and works so much better.

Aircraft manuals should be concise. Airlines have standard operating procedures and their crews are almost like human robots. Every part of the operation is a standardized procedure and there is very little room for interpretation, human judgment or deviation. With tens of thousands of crews flying tens of thousands of flights every day, this is how your operations must be. You want everything to be simple and standardized, guaranteed to have the same desired outcome each and every time.

General Aviation has a far worse safety record than the airlines and while there may be many reasons for that and no simple solutions, I personally think that the undue complexity of aircraft manuals and checklists is a contributing factor. General Aviation manuals aren’t simple and standardized: they’re complex and verbose.

As a ferry pilot I fly many different aircraft so I consider use of checklists even more important for me than for the average pilot who typically flies the same airplane. I recently picked up a factory new Cessna 172 and the only checklist in the airplane was the factory-issued normal and emergency procedures out of the Cessna 172 POH, so that’s what I used to start the trip.

Take a look at this C172 “before takeoff” checklist, I’ve pasted it out of a copy of a late-model, G1000 Cessna 172SP POH:

BEFORE TAKEOFF
1. Parking Brake – SET
2. Pilot and Passenger Seat Backs – MOST UPRIGHT POSITION
3. Seats and Seat Belts – CHECK SECURE
4. Cabin Doors – CLOSED and LOCKED
5. Flight Controls – FREE and CORRECT
6. Flight Instruments (PFD) – CHECK (no red X’s)
7. Altimeters:
a. PFD (BARO) – SET
b. Standby Altimeter – SET
8. ALT SEL – SET
9. Standby Flight Instruments – CHECK
10. Fuel Quantity – CHECK (verify level is correct)
NOTE
Flight is not recommended when both fuel quantity
indicators are in the yellow band range.
11. Mixture Control – RICH
12. FUEL SELECTOR Valve – SET BOTH
13. Autopilot – ENGAGE (if installed)
(push AP button on either PFD or MFD bezel)
14. Flight Controls – CHECK (verify autopilot can be overpowered in
both pitch and roll axes)
(Continued Next Page)

BEFORE TAKEOFF (Continued)
15. A/P TRIM DISC Button – PRESS (if installed)
(verify autopilot disengages and aural alert is heard)
16. Flight Director – OFF (if installed)
(push FD button on either PFD or MFD bezel)
17. Elevator Trim Control – SET FOR TAKEOFF
18. Throttle Control – 1800 RPM
a. MAGNETOS Switch – CHECK (RPM drop should not
exceed 150 RPM on either magneto or 50 RPM differential
between magnetos)
b. VAC Indicator – CHECK
c. Engine Indicators – CHECK
d. Ammeters and Voltmeters – CHECK
19. Annunciators – CHECK (verify no annunciators are shown)
20. Throttle Control – CHECK IDLE
21. Throttle Control – 1000 RPM or LESS
22. Throttle Control Friction Lock – ADJUST
23. COM Frequency(s) – SET
24. NAV Frequency(s) – SET
25. FMS/GPS Flight Plan – AS DESIRED
NOTE
Check GPS availability on AUX-GPS STATUS page. No
annunciation is provided for loss of GPS2.
26. XPDR – SET
(Continued Next Page)
BEFORE TAKEOFF (Continued)
27. CDI Softkey – SELECT NAV SOURCE
CAUTION
THE G1000 HSI SHOWS A COURSE DEVIATION
INDICATOR FOR THE SELECTED GPS, NAV 1 OR NAV 2
NAVIGATION SOURCE. THE G1000 HSI DOES NOT
PROVIDE A WARNING FLAG WHEN A VALID
NAVIGATION SIGNAL IS NOT BEING SUPPLIED TO THE
INDICATOR. WHEN A VALID NAVIGATION SIGNAL IS
NOT BEING SUPPLIED, THE COURSE DEVIATION BAR
(D-BAR) PART OF THE INDICATOR IS NOT SHOWN ON
THE HSI COMPASS CARD. THE MISSING D-BAR IS
CONSIDERED TO BE THE WARNING FLAG.
WARNING
WHEN THE AUTOPILOT IS ENGAGED IN NAV, APR OR
BC OPERATING MODES, IF THE HSI NAVIGATION
SOURCE IS CHANGED MANUALLY, USING THE CDI
SOFTKEY, THE CHANGE WILL INTERRUPT THE
NAVIGATION SIGNAL TO THE AUTOPILOT AND WILL
CAUSE THE AUTOPILOT TO REVERT TO ROL MODE
OPERATION. NO AURAL ALERT WILL BE PROVIDED.
IN ROL MODE, THE AUTOPILOT WILL ONLY KEEP THE
WINGS LEVEL AND WILL NOT CORRECT THE
AIRPLANE HEADING OR COURSE. SET THE HDG BUG
TO THE CORRECT HEADING AND SELECT THE
CORRECT NAVIGATION SOURCE ON THE HSI, USING
THE CDI SOFTKEY, BEFORE ENGAGING THE
AUTOPILOT IN ANY OTHER OPERATING MODE.
28. CABIN PWR 12V Switch – OFF
29. Wing Flaps – UP – 10° (10° preferred)
30. Cabin Windows – CLOSED and LOCKED
31. STROBE Light Switch – ON
32. Brakes – RELEASE

Seriously, 3 pages and 32 items is your “before takeoff” checklist, a hand full of warnings and cautions and then you omit the most important item:

“TAKEOFF BRIEFING – COMPLETE”.

Sorry Cessna, I love you guys and I’ve flown your airplanes practically all over God’s creation but the “before takeoff” checklist in a C172 should not be 3 pages long, it should not have 32 items in it but it darn well ought to have a takeoff briefing in it!

Take a look by comparison at the “before takeoff” checklist out of a Maule M7 manual:

BEFORE TAKEOFF
1. Seat Belt and Shoulder Harnesses – RECHECK FASTENED
2. Doors – CLOSED and LATCHED
3. Fuel Selector Value – FULLER TANK or BOTH (If Equal)
4. Flaps – SET FOR TAKEOFF (MAX 24 Degrees/2nd Notch)
5. Trim Controls – SET FOR TAKEOFF
6. Flight Controls – CHECK FREE and CORRECT
7. Crew Briefing – COMPLETE
a. Departure
b. Emergencies
8. Radios and NAV Equipment – AS DESIRED
9. Altimeter – SET
10. Mixture Control – FULL RICH
11. Propeller Control – HIGH RPM
12. Alternate Air Control – IN and LOCKED
13. Anti-collision Light – ON
14. Pulse Lights – As Required
15. Transponder – ALT
16. Engine Instruments – CHECK
17. Attitude Indicator – CHECK ERECT
18. Directional Gyro – CHECK and SET
19. Parking Brake – OFF

The Maule M7 “before takeoff” checklist is half a page long and includes the most important item on any “before takeoff” checklist: the takeoff briefing. Maule also does a better job than Cessna by moving the run-up checklist to a separate checklist. Many times you won’t be doing the run-up just before takeoff but in a designated run-up area somewhere, a run-up is a different activity than a “before takeoff” check. The “before takeoff” checklist should simply have an item “runup – complete”.

The “before takeoff” phase of flight is one of the more critical phases of flight. Things like runway incursions, airspace violations, stall-spin accidents, can all be partly attributed to pilot error or distractions. Therefor the “before takeoff” checklist needs to be short and sweet and cover only the things that are important at that point in the flight, no extraneous stuff, no distractions. Same holds true for the approach checklist and landing checklists. By-the-way, the C172 checklist also omits the “approach briefing” just like they omit the “takeoff briefing”.

If General Aviation safety is to improve – especially considering the complexity and capability of current aircraft – pilots need to operate more by standard operating procedures, short and sweet, just like the airlines. Wordy and complex manuals do not accomplish that.

Now you might say that the complex manuals are a product of trial lawyers but if that’s true somebody needs to put all the trial lawyers in a room together and explain to them that complex and wordy manuals don’t help safety, they hurt it.

The most important reason why complex manuals hurt General Aviation safety is because the manuals are so complex nobody uses them. At the end of my first day of flying on my last trip I bought a much better aftermarket C172 checklist because the factory manual is so bad, but how many pilots do you think simply put the manual in the back of the seat pocket and never look at a checklist again? If you want pilots to use checklists, they must be written for the real world. Think pilots will sit at the departure end of a busy runway and read 3 pages of manual? And if they did, that much heads-down time at such a critical juncture would be more detrimental to safety than anything.

Another problem with complex manuals is that they increase the potential to overlook something important amids all the frivolous stuff (“throttle friction lock – adjust” seriously?).

One of my recent customers almost died in a Piper Mirage many years ago after having a complete electrical failure in actual IMC in Denmark. When the pilot told me his story he made no excuses – he had overlooked one step on the “starting engines with external power” checklist. What happened is that this pilot left a master switch on after a flight and drained the battery in an earlier model Piper Mirage. After starting the engine with external power on his next flight he missed the step on the checklist where you are supposed to check if the battery is charging. He had checked alternator output on both alternators but not if the battery was charging. Due to a battery-powered relay in the system the battery would not come online if it was completely dead, even with 2 operating alternators. In case you’re not familiar with small aircraft electrical systems, the battery is supposed to act like a “cushion” so that the alternators don’t have to respond immediately to each and every variation in electrical system demand. Because the battery never came online and didn’t provide this “cushion” to the alternators, shortly after takeoff on this fateful flight both alternators simultaneously quit and the pilot found himself in actual IMC with no electrical power at all. Only because he is an excellent pilot, had a handheld emergency radio, and perhaps because somebody up above decided it wasn’t his time, did he (and his passengers) live to tell me this story. But if the “starting engine with external power” checklist had been short and simple, maybe the entire episode wouldn’t have happened, maybe he would have noticed the battery wasn’t charging, shut down and put a battery charger on the airplane for a few hours. A simpler checklist might have saved the day.

Just my humble opinion, when it comes to aircraft POH’s and checklists, simple is better.

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One Comment leave one →
  1. January 31, 2012 3:18 pm

    Hi! I’m a Private Pilot in Brazil (in fact I JUST got my license… I have precisely ZERO flight hours after that, since I’m outside my country now and dreaming to return so I can fly again…). This blog is helping me to feel a little bit more “at home” again, reading some good thinking about the daily life of GA. And helping me improve my flying philosophy even before my first flight now as a pilot! Thank you very much! :)

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