IT SHOULD NOT HAPPEN TO YOU

COMANCHE ACCIDENTS, 5.2003, AND A CASE

by Omri Talmon

COMANCHE ACCIDENTS, 5.2003

5.1 Date: 05/06/2003.  Acft:  PA-24-180. DESCRIPTION: ACFT ON LANDING, GEAR COLLAPSED, OTHER CIRCUMSTANCES ARE UNKNOWN, AURORA, CA.  Damage: Unknown.  One occupant, no injuries.

5.2 Date: 05/12/2003.  Acft: PA-24.  DESCRIPTION: ACFT LANDED GEAR UP, BOLIVAR, TN.  Damage: Minor.  Two occupants, no injuries.

5.3 Date: 05/19/2003.  Acft: PA-24-260.  Description: ACFT UPON LANDING, HIT A TREE AND FLIPPED OVER, OTHER CIRCUMSTANCES ARE uNKNOWN, BLANEY PARK AIRPORT, UPPER PENINSULA, MI.  Damage: Substantial.  One occupant, minor injuries.

5.4 Date: 05/21/2003.  Acft: PA-30.  DESCRIPTION: ACFT MADE AN EMERGENCY LANDING WHEN ONE ENGINE LOST POWER, OTHER CIRCUMSTANCES ARE UNKNOWN, BAGDAD, AZ.  Damage: Minor.  One occupant, no injuries.

5.5 Date: 05/25/2003.  Acft: PA-24-180.  DESCRIPTION: ACFT ON LANDING, GEAR COLLAPSED, OTHER CIRCUMSTANCES ARE UNKNOWN, KITTY HAWK ESTATES, SUWANEE COUNTY, FL.  Damage: Unknown.  Two occupants, no injuries.

A CASE

NTSB REPORT

Accident occurred Friday, September 25, 1998 in LAMAR, MO
Probable Cause Approval Date: 2/16/01
Aircraft: Piper PA-24, Injuries: 2 Uninjured.

The pilot reported she entered the landing pattern and performed the pre-landing checklist.  She lowered the landing gear, pulled carburetor heat on, turned the fuel pump on, switched to the fullest fuel tank, and reduced power.  She turned from base to final and added a little power, but 'there wasn't any power there.' The second pilot switched magnetos and tried to restart the engine, but was unsuccessful.  The second pilot took control of the airplane and turned to the left to land in a soybean field, since there were power lines and a railroad track between the airplane and the runway.  The airplane landed in a left wing low attitude and the left wing hit the ground before the airplane skidded to a stop.  All engine, propeller controls and flight controls were verified as being intact and operable.  The fuel selector was found in the OFF position.  The pilot and second pilot were asked whether either of them had moved the fuel selector to OFF after the accident had occurred and both stated they had not.  The fuel drain plug from the carburetor was removed and only a trace of fuel, two or three drops, came out. 

The National Transportation Safety Board determines the probable cause(s) of this accident as follows: the pilot improperly positioned the fuel selector to the closed position causing fuel starvation.

Full Narrative

On September 25, 1998, at 2340 central daylight time, a Piper PA-24, N5029P, was substantially damaged when the engine lost power and it landed in a bean field 400 yards short of runway 21 at Lamar Municipal Airport, Lamar, Missouri.  The private pilot and the second pilot were not injured.  The 14 CFR Part 91 flight departed from Bartlesville, Oklahoma, and was en route to Lamar.  Visual meteorological conditions prevailed and no flight plan was filed.

The pilot reported the flight from Bartlesville to Lamar was uneventful until the airplane entered the landing pattern at Lamar.  The pilot reported she entered the landing pattern and performed the pre-landing checklist.  She lowered the landing gear, pulled carburetor heat on, turned the fuel pump on, switched to the fullest fuel tank, and reduced power.  She reported she turned from downwind to base and noticed she was low on the approach.  She reported she added power to increase the glide range.  She reported she turned from base to final and added a little power, but "there wasn't any power there." She reported the second pilot switched magnetos and tried to restart the engine, but was unsuccessful. The second pilot took control of the airplane and turned to the left to land in a soybean field since there were powerlines and a railroad track between the airplane and the runway. The airplane landed in a left wing low attitude and the left wing hit the ground before the airplane skidded to a stop.  The pilot reported she turned the switch off as she evacuated the airplane. 

The second pilot reported he did a scan of the lower panel when the pilot reported that the airplane had lost power.  The second pilot checked the boost pump, carburetor heat, magnetos, throttle, propeller, and mixture, but could not find anything wrong.  He took control of the airplane and put in full flaps.  He reported the drag of the beans on the left wing made the airplane yaw to the left and "probably made the lading gear failure.  He reported that the pilot shut everything off when they exited the airplane. 

An Airworthiness Inspector from the Federal Aviation Administration inspected the airplane.  He reported that both fuel tanks were full, with only thirty minutes of fuel burned from one tank.  All engine, propeller controls and flight controls were verified as being intact and operable.  The fuel selector was found in the OFF position. 

The inspector questioned the pilot and second pilot whether either of them had moved the fuel selector to OFF after the accident had occurred.  The inspector reported that both emphatically stated they had not.  The inspector removed the fuel drain plug from the carburetor and only a trace of fuel, two or three drops, came out. 

DISCUSSION

Upon entering the pattern, the pilot "performed the pre-landing checklist.     She lowered the landing gear, pulled carburetor heat on, turned the fuel pump on, switched to the fullest fuel tank, and reduced power".  This seems to be flying by the book. Is it really?

Time and again it has been emphasized that switching fuel tanks is not a risk free operation.  All kinds of mistakes can happen as well as mechanical problems, like the handle coming off the selector or the valve getting stuck in the middle between two positions.   Therefore, if it is necessary to switch fuel tanks it should be done, if possible, at a safe altitude while being at full attention to take action if something happens to the engine within the first two minutes after the procedure.

Further, the book indeed recommends selecting the fullest tank for landing.  In this case, there was no empty or half empty tank.     One was full and the other, nearly full.  Therefore, switching tanks was not necessary since both tanks had sufficient fuel.  Also, in the pattern is no time to be switching tanks; this most certainly would be contrary to a safe operating procedure.

We are told -- and rightly so -- that if the engine loses power after a certain operation, we should immediately restore the former configuration.  If it had been attempted in this case, the wrong fuel valve position would have been immediately detected.

The "second pilot" reported that he "checked the boost pump, carburetor heat, magnetos, throttle, propeller, and mixture, but could not find anything wrong".     Didn't it occur to him to look down at the fuel tank selector?  There can be many reasons for an engine to lose power but the most frequent one is fuel starvation.     The fuel valve would be one of the first items, if not the first one, to be checked.

LESSONS

Switching fuel tanks has some built-in risks and should not be taken lightly.

The normal scan, and in particular an emergency scan, needs to include the fuel tank selector.

PROVERB

Keep looking around, there's always something you missed

Omri Talmon, born in 1936, lives in Tel Aviv, Israel. He holds degrees in engineering, business administration and accounting. Presently a consultant, he worked for many years as an executive for several hi-tech companies.  Omri is a private pilot with both Israeli and U.S. certificates.  His ratings include SEL, MEL, Instrument, Glider, and CFI (glider).  Since 1974 he owns and flies a 1966 PA-30-B, registration 4X-CAO.