After an uneventful cross-country flight in a Piper Cherokee, the pilot began the landing descent into Rock Springs, Wyo., by reducing engine power.
When the plane approached the base leg of the traffic pattern, he performed the landing checklist, which included switching the fuel selector valve to the left tip tank. While turning the base to final leg of the traffic pattern, he decided that he was too low and applied full power to stop the descent.
The engine did not respond, but instead lost power. The pilot made a forced landing in rough terrain. The Piper went through a fence and hit a berm, substantially damaging both wings.
Data extracted from the engine monitor, as well as the minimal quantities of fuel recovered from the fuel system, were consistent with a fuel starvation event.
After the accident, the pilot told investigators that he may have inadvertently starved the engine of fuel during the approach by turning the fuel selector valve beyond its left tip tank travel limit toward its OFF position. The fuel selector lever was fitted with an interlock mechanism to prevent a pilot from inadvertently shutting off the fuel in this manner. However, examination revealed that the mechanism had shifted and the fuel selector lever could be moved to a position between the left tip tank and the OFF detent without engaging the interlock, which could result in an interruption of fuel flow to the engine.
The NTSB attributed the accident to the pilot’s inadvertent movement of the fuel selector valve beyond its tank detent, which resulted in a total loss of engine power due to fuel starvation. Contributing to the accident was the failure of the fuel selector interlock mechanism.
NTSB Identification: WPR13LA094
Folks making comments about fuel running away from the fuel pickup while turning are not thinking this through. If you are in a coordinated turn the fuel will always remain in the same place. Up wing, down wing; it does not matter. Being on the fullest tank does matter. If you plan to slip the plane down to the runway, that’s a different thing. In a slip the fuel will shift outward in the tank in the direction of the slip. It could, in fact be the up wing that fuel becomes up-ported, but this would be a skid, which something you do not want to do when slow and at low altitude.
The Pa-22 is the same set up unless you get the Dakota Cub Fuel selector which has “both”. With the standard set up “No take off or landing on right tank with less than 2/3 in that tank. I run up and take off on left tank. Switch to right at 1000 ft AGL or cruise climb and just run that till it is near empty. Switch back to left and start thinking about a place to get more gas.
The pilots operating manual & aircraft on Cherokee’s with 4 tanks is plaquered against take off or landing on tip tanks.
I remember my flight instructor telling me how his close friend died from an accident stemming from basically the same scenario, with one difference. Instead of remembering to switch the tanks on landing, that pilot forgot to and thus starved the engine while banking to land. To avoid any issues like this, or others while in the traffic pattern, I always make sure to complete my “before landing checklist” prior to entering the traffic pattern. This way I’m not jeopardizing other airplanes in the pattern and I still have altitude to try to fix any issues. I use the GLUMP mnemonic (Gas on both, Landing lights on, Undercarriage down and welded, Mixture rich, Propeller high RPM – and passengers with seatbelts on and prepared for sterile cockpit.
Cherokees don’t have “Gas Both” selections; it’s ‘Right’ or ‘Left’ and, of course, ‘Off”.
I trained in Cherokees and this is what I was taught:
Engine start on best tank, run-up on second tank, back to best tank for launch.
Ration fuel to enter pattern on ‘Left’ tank; reason is, the switch from ‘Left’ to ‘Right’
is a 1/4 turn clockwise, AWAY from ‘Off’ position. In the event the engine “coughs”
while in the pattern, the fuel switch is automatic; reach down to the selector on the
left side panel and slam it to the right. No need to think about it; just do it.
Fortunately, I’ve never had a fuel starvation issue. But if I did, I think I’d be better prepared by forming habits such as this.
Glad he walked away…
I suggest a read of the NTSB Accident report and view the fuel selector switch photos in the report. The accident Piper PA-28-235 Cherokee had two 17 gallon tip tanks, and a fuel transfer switch to accommodate the four fuel tanks. This model should not be landed using tip tank fuel.
I learned to fly on the PA-28-140 50 years ago and have kept up with the PA-28 variants.
Start on the left tank, end the flight on the right, EVERY TIME! Standard turns in the traffic pattern are to the left so fuel in the right wing is running downhill toward the pickup. Do the fuel selector change while losing altitude to pattern altitude 3 to 5 miles out, EVERY TIME! If you mess something up you have time and altitude to deal with it. If you’re doing a non standard pattern, turns to the right, you know it’s nonstandard and the hair stands up on the back of your neck EVERY TIME. You have to look for traffic in an unusual direction, your visual cues for attitude and distance to the runway on the aircraft structure are different AND you leave the fuel selector on the left tank.