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what was the fuel flow? do you have any data from a Chelton or JPI to share?
Jeff Edwards
VA-34, VA 176
LIVP 1300 hours
-----Original Message-----
From: William Miller <cwfmd@yahoo.com>
To: lml@lancaironline.net
Sent: Sat, 16 May 2009 5:22 am
Subject: [LML] flameout at FL220
I experienced an engine failure while leveling off at FL220 this afternoon. I
have almost 200 hours over 15 months on this 2007 IV-P with the TSIO-550B
engine, which has 450TT and 220 STOH. We had been tweaking the baffles and
checking the CHT probes by swapping probes 5 with 3 and 2 with 4. We had just
seen a great improvement in CHTs with the modifications. I was in the process of
climbing to FL220 to get some cruise data at 75, 65, and 55 %. Because of the
typical ISA+25 Gulf Coast afternoon temps, I had to level off at 12 and 18 for
about 4-5 minutes to let the oil temp cool off. The climb temps looked good
passing 200 and 210 to continue to 220. When I reached 220 and began the level
off, immediately I noticed a very sudden rise in CHTs and EGTs from about 400
where I had expeced them to peak in the climb. 6 + 8 elashing red temps will get
your attention right away. (I have the early warnings set at 420 and 1700). The
temps came rapidly up to just
below red line in the high 430s. I have not seen this pattern before in 200
hours in this airplane and with many hot day climbs to the FL200s. I began to
slowly reduce throttle, trying to guess whether it was better to keep cooling
fuel flow and high power or throttle back to counter the rising temps.
As I pulled the throttle back, I was able to arrrest the rise but soon noticed
the EGTs rapidly dropping. At this point there was no response to throttle
inputs. I notified center of my descent, to which he replied that I should ask
for a descent clearance first. I replied that I was aware of that procedure, but
believed I had a powerplant failure and did not have an option. I turned toward
PSX, the nearest long piece of concrete and pulled the prop back for max glide.
The engine windmills nicely at max glide of 120KIAS( I have wondered if it might
stop the windmill at 120, best L/D and then loss of oil pressure would send the
prop back to flat pitch). I got out the engine fail/airstart checklist and
switched from the left to the right tank. I notified center of my intention to
airstart. Passing 17K, I recall telling him I had about 17 minutes and could
easily make the airport at 17 miles. Shortly thereafter at 16500 the engine
responded to throttle
inputs, but initially roughly like a cold start. Slowly allowing the engine to
rewarm, I got normal power back. Satisfied with the recovery and airstart, I
turned back to homebase about 35 milees away and shot a precautionary approach
to high key at Houston Southwest.
Our best guess after review with my mechanic and a conversation with Tim Wilson
at Lancair was that the culprit was temporary fuel starvation. I am guessing
that the sudden rise in the EGTs and CHTs was the result of an uncommanded
leaning of the mixture as the fuel supply dropped. I did not catch a good record
of the fuel flow until after the successful recovery. From then on it was
normal. The tanks both had been filled before the previous flight and only
about ten gals had been used from both tanks, so there was about 42 gal. in
each. Preflights indicated no obstruction to the wingtip vents and this was true
postflight. Fuel samples are done first flight of each day and this was the
third flight today. The low boost was on passing 10,000 in the climb in
accordance with the checklist. I did not get around to trying the high boost
because the failure appeared to clear by switching tanks. when I reached a safe
glide range, I tried switching back to the
left tank and saw no change in fuel flow. I suspect a fuel vent blockage at the
freezing level, but I had not flown through any visible moisture this afternoon.
Tops of the towering CU was about 10K widely scattered, so they were easy to
dodge and avoid moisture and ice in the climb. The engine behaved perfectly
thereafter and responded well to clearing procedures during the precautionary
approach.
1. Anybody see this pattern before?
2. Any suggestions on troubleshooting or where to look for the cause?
3. What would you check prior to continuing operations other than a thorough
engine inspection and fuel system check?
Thanks for the good information and guidance on the LML,
Bill Miller
USN Test Pilot
L-IVP, 191 hours
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