DK's accident
Hallo again Gentlemen,
First for Gary ... yes, the report you have is the one I would have posted on our site, but no doubt it is far too long. It will appear in the July edition of BLADES anyway for those wanting to read the full details.
Meantime to summarise.
Invitation to Utah to display and promote my scholarship DVD. Once there I was immediately advised of the density problem by the local pilots. I've flown at high DAs before, but nothing as severe as 5,700 airfield elevation and temperatures almost in three figures.
Accordingly, I arranged a longish practice, (over an hour) on the Schweizer 300C model at a 5,500 ft airfield and 80 degrees. I was accompanied by the operator and take off weight was around 1,850 lbs. I practiced all the manoeuvres to be flown the following day, after which I decided to modify the various height & speed 'Gate' numbers by 10 knots and 50 feet minimum display height.
I should have insisted on a local practice at West Desert airfield (5,700 ft), but circumstances made it difficult. It was decided to make the display late morning before the temperatures hit maximum.
In the event the operator and I were late arriving, (fuel) and the display was now scheduled for 13.00 hrs. To additionally offset the local DA, I decided to offload fuel to 10 gallons for the display, and also remove all surplus equipment, fire extinguisher, controls, GPS and headsets. In the event the most fuel that could be offloaded still left me with 30 gallons.
Since I was something of the centre of attention having travelled 5000 miles to display, I was unable to have my preferred five minutes 'quiet time' prior to my flight.
The light breeze was 10-12 knots, mostly down the runway, right to left as I faced the crowd line.
I commenced the display some 300 lbs less than in practice with a display area inspection circuit at 50 feet. Satisfied, I settled on the tarmac runway to commence the standard opening 'pirouette' I was actually surprised at the performance available at the lighter weight and completed my usual five pedal rotations with the left skid tip in contact with the tarmac.
I pulled aft cyclic and collective to lift into the rearward climbing spiral and once again, I had sufficient power to perform the nil-translational lift, out of ground effect manoeuvre.
I continued the manoeuvre to 300 feet and pulled back away from the crowd to position for the fast run-in along the 'B' axis back toward the crowd.
I'd made quite a few small mistakes in my planning, the fuel, the practice venue, no thinking time and doing my practices with the operator on board, but as I commenced the run in I made the major mistake that was the cause of the accident. I had drifted some 100 yards downwind to the crowd's left which required a more acute angle 'run-in' and a greater turn in the 270 degree wing-over. The turn would now require perhaps 300 degrees.
For some reason, and I now think I was lulled by what I thought seemed a fairly normal performance, I launched myself straight into 'display mode' and failed to run in at the 50 feet I had decided and neither did I reach the higher 'gate' speed before commencing the cyclic 'pull-up' for the 270 degree wing-over. Looking at the video, I can see that I was losing height in the turn more rapidly than normal and in making the longer turn, I had lost even more height.
However, even in the steep descent, at no stage did I think the manoeuvre was going wrong, until the skids actually made contact. I didn't make any changes to either the collective or cyclic.
On impact the cabin filled with desert dust and for a moment I wasn't aware I was almost inverted. I spent quite a few seconds trying to locate the fuel boost pump switch, and having stopped it running, I looked for the master switch. I tried several before I found the right one, but thinking now, it would have helped if the switch was more prominent or coloured red, rather like the Enstrom. I never did locate the fuel cock and realising that all my limbs were mobile, I released the safety straps and scrambled clear of the wreck.
It says a great deal for the crashworthiness of the little Schweizer 300 that I wasn't badly injured or worse. And of course if I had been thinking properly, I'd have realised the master switch would have stopped the fuel pump anyway.
So the main reason for the accident was my failue to make sufficient allowance for the temperature and altitude conditions, and while I had been well aware of the density, I wasn't nearly aware enough and I didn't stick to the speed & height changes I'd decided on.
I believe now that had I stuck exactly to my changed height & speed display numbers, I would probably have completed the wing-over manoeuvre safely as I have at least a thousand times. (actually a lot more)
The other factor was having to make a longer turn at the top of the manoeuvre, which in normal density conditions would not have presented a problem.
Anyway, the above is the abridged accident report, and as is often the case, my accident was triggered by a series of poor decisions, but nevertheless it was the density altitude that actually nailed me.
I'm sure I'll meet many of you in the coming months, and will be able to amplify some of the above aspects in conversation.
Thanks again for the many kind and encouraging words posted here. They are more than appreciated.
Best wishes & safe flying to you all.
Dennis Kenyon.