IT SHOULD NOT HAPPEN TO YOU

COMANCHE ACCIDENTS, 1.2003

by Omri Talmon

Comanche Accidents, 1.2003

1.1 Date: 01/04/2003. Acft: PA-24-     Descr: ACFT LANDED GEAR UP.  Damage: Minor . One POB, no injuries.

1.2 Date: 01/05/2003. Acft: PA-30.   Descr.: PILOT STATED THAT AFTER LANDING RWY 32 WITH A TAILWIND,  HIS RECOLLECTION  WAS 23008, HE WAS PUMPING THE BRAKES TO STOP AND RANOFF THE END OF THE RUNWAY, DAMAGING TWO THRESHOLD LIGHTS.  Damage: None. One POB, no injuries.

1.3 Date: 01/14/2003. Acft: PA-30. Descr: ACFT EXPERIENCED ELECTRICAL FAILURE AND LANDED GEAR UP. Damage: Substantial. Two POB, no injuries.

1.4 Date: 01/12/2003. Acft: PA-24-250. Description: ACFT LANDED GEAR UP. MINOR ACFT DAMAGE AND NO INJURIES TO THE FOUR OCCUPANTS. Damage: Minor. Four POB, no injuries.

A CASE

NTSB Report

Accident occurred Tuesday, February 12, 2002 at Scappoose, OR. Aircraft: Piper PA-24-180. Injuries: 1 Fatal, 1 Minor.

The pilot reported that he hand propped the engine because the electric starter would not start the engine. He instructed his passenger, seated in the right seat, in the use of the "T" handle brake system, which had to be pushed in for the Johnson brake bar to work. The pilot then set the throttle between one-quarter and three-eighths of an inch. Once the engine started, the pilot observed that the engine produced high power and the aircraft began to move forward. The aircraft knocked down the pilot as it accelerated across the airport. The aircraft crossed the runway and a taxiway and collided with a fence and trees in a park to the west side of the airport. The pilot reported that he did not understand how the brake could have been released. No tie-downs or wheel chocks were used.

The National Transportation Safety Board determines the probable cause(s) of this accident as follows:

The pilot's failure to tie down the aircraft prior to hand propping the engine. Factors were a fence, trees, and the pilot's inadequate preflight planning/preparation.

FULL NARRATIVE

On February 12, 2002, about 1500 Pacific standard time, a Piper PA-24-180, registered to and operated by the pilot as a 14 CFR Part 91 personal flight, sustained substantial damage when it collided with a fence and trees at the Scappoose Industrial Airpark, Scappoose, Oregon. Visual meteorological conditions prevailed at the time and no flight plan was filed. The private pilot received minor injuries and the passenger was fatally injured.

During a telephone interview and subsequent written statement, the pilot reported that after fueling, attempts to start the engine with the electric starter were unsuccessful, therefore, he decided to hand prop the engine. The pilot stated that he "pulled the prop through six to seven times" to purge the fuel in the cylinders. After this was completed, he instructed his passenger, seated in the right seat, to turn on the master switch. The pilot then turned the magnetos to the both on position, enriched the mixture, and opened the throttle one-quarter to three-eighths of an inch. The pilot also instructed his passenger on the operation of the "T" handle brake system, which had to be pushed in for the Johnson brake bar to work. The pilot stated that he then "pushed on the cowl to verify the brake was set. It was. I pulled the prop, and the engine instantly started". The pilot then started to walk around the wing when the engine RPM increased to high RPM and the airplane began to move forward. The wing knocked the pilot down and the airplane continued to travel across the ramp toward the runway. The aircraft crossed the runway and a taxiway before colliding with a fence and subsequently trees in a park on the west side of the airport.

The aircraft fuselage came to rest against a tree. Both wings and the left horizontal stabilizer separated from the fuselage.

The pilot stated that he does not know how the brake could have been released, and he reported no mechanical malfunction or failure on the NTSB Pilot/Operator Aircraft Accident Report Form 6120.1/2. No ground tie down ropes or wheel chocks were used.

An automated weather observation at Scappoose reported at 1453, clear skies with 10 miles visibility and wind from 330 degrees at 3 knots.

Witnesses at the fuel pumps, reported to a Scappoose Police Department Officer, that the aircraft was traveling approximately 70 to 80 miles per hour when it collided with the fence and trees.

MY FURTHER INVESTIGATION

Scappoose is well inside Comanche territory. One Comanchero from the neighborhood was able to add additional information as received from witnesses:

After fueling the airplane, the engine would not start. The pilot moved the airplane away from the fuel pumps to hand prop the engine. The witness said that it seemed he had a dead battery and the gas pump attendant had refused to hand prop it for him. The passenger was an elderly gentleman (80 years old) who the pilot had met in church and was taking him for a flight as a favor. Another reliable witness, who was at the fuel pumps, reported that during the event, the airplane become airborne about four feet above the ground just prior to the collision with the fence. This witness, a Bonanza pilot, reported that when the engine was first started it was ticking over properly and then suddenly went to full power. This suggested to him that the person inside the plane did the wrong thing with the throttle. He noted further that there is a children's playground just beyond the stand of trees the plane impacted. There were no children present at the time.

A second Comanchero took several photos of the aircraft, two of which are attached:

The ignoble resting place for what's left of a nice Comanche--an aircraft salvage yard.  Note the bent portion of the left wing spar. Both wings and the left stabilator are separated from the fuselage, stacked against the fence.

Destruction is substantial.  Windshield is gone, and there are portions of chain link fence wrapped around the prop.

MY DISCUSSION

This tragic accident brings to light several important issues.

Hand propping an aircraft is an art by itself and requires proper knowledge and training.

Further, two persons are required; one outside, the second at the controls, both competent in what they are about to do and well acquainted with the procedure. There is no room for shortcuts as this is an inherently dangerous operation. An external power connection may be a better and safer solution.

An aircraft should never, never be left with the engine(s) running and no properly checked out person at the controls.

Finally, when we find there is a failure of a system or component in our aircraft, the best technique is to fix it first and proceed with the flight later.  Very seldom--or never (in our type of flying)—are there such circumstances which absolutely mandate departure with a defective aircraft.

LESSONS

Hand propping is a dangerous operation and should be avoided unless absolutely necessary.

If not installed – an external power plug is an option to be considered.

When in doubt – there is no doubt. Don't go.

PROVERB

Rushing is the brother of regret (from Bedouin folklore)

Omri Talmon, born 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.