The final report with a determination of probable cause is not expected to be out till May, although its unlikley it will be more revealing than the current "factual" report. Personally, it leaves me with more questions than answers after reviewing the "facts" it disclosed:
- the point of impact was .37 nm after the departure end of the runway. If on centerline, that would put it right where the trees began, yet the map Byron's posted above suggest the Mooney veered left of centerline and into the tree area prematurely. (see a google earth view if curious)
- The bigger question though in my mind, is per the departure procedure for runway 23, they needed a climb gradient of 240'/nm or a climb rate which translates approximately to about 350fpm at Vy or initially 260 FPM at Vx. At an airport elevation under 2000' and 186 lbs under gross (max gross was 2900 lb) that should have been easily doable! Gear up or down.Yet they apparently never got more than approx 100' agl to hit the tree tops. An older J POH suggest a climb rate of 700+fpm. Why was their climb rate so anemic?? Could the nose have been held too high near stall to prevent acceleration to Vx & Vy? From the interview, with the survivor we read:
- (FAA phone interview the day after on 5/10) "upon lift off Mr. Kisseloff stated that the stall horn sounded. Mr. Kisseloff stated that the stall horn was sounding the entire portion of the climb, Mr. Kisseloff stated that the left wing struck a tree and the aircraft crashed immediately afterward."
- (from NTSB phone interview later on 5/15) "The airplane became airborne at the departure end numbers, just before crossing over the displaced threshold. Immediately (about a second) after liftoff, the stall warning activated. Mr. Sheridan was “unable to recover from the stall.” They approached the trees at the end of the runway, and the airplane began a turn to the left of runway centerline. Mr. Kisseloff could see the trees approaching, and estimated that they were about 3 feet above the trees. He stated that they were probably descending when they hit the trees. The left wing struck a tree (he saw sparks from the left wing during the tree impact) and they “went down.” "
Or was the engine not putting out full rated power? They say very little about the engine, including nothing about TSMOH - only "All cylinders were examined using a lighted bore scope; no defects were observed. Nothing was observed during the course of the examination that would have precluded this engine from making rated power prior to impact." Still leaves me wondering if the cam allowed normal valve height to enable full power; but I’ll assume their inspection and conclusion was accurate.
Sure there are other decisions that could have resulted in a different outcome, including taking off downhill (that was brought up in the cockpit per the survivor) and using all of the runway. But since we know they got airborne fine, the real issue seems to be their anemic climb rate. The only plausible explanation offered in the factual report is being at too slow of an airspeed or too high of a climb angle based on the stall horn being on continuously. Getting off the extended centerline did not help either. We’ll soon see what they conclude in the final report in May.
So very sad!