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Posted for Sky2high@aol.com:
In a message dated 12/13/2003 8:50:29 PM Central Standard Time, bill_kennedy_3@hotmail.com writes:
Are there any approved numbers for the two seat Lancairs for high key, airspeed and configuration (engine out landing). Someone mentioned an insurance program check out program with procedures. Someone also mentioned 2500 AGL which seems a little high. My gut feeling is that the altitude should give you a little extra energy, but not require a large circle -- maybe 1500 AGL and 100-110 knots. I liked the suggestion of starting by crossing the landing point rather than aligning with the runway. That would give you a couple more options. I think I'll give that a try.
If anyone answers, would you be specific about the source of your procedure. I like to know if it's your personal preference or an accepted procedure by Lancair or whoever.
Bill,
Before anyone answers with hard facts, let me toss out some surmising:
For Lancair 320 only:
At higher gross weights (about 1750 lbs), I see about 105 KIAS as best speed for max L/D clean. At idle power simulating 0-thrust (maybe someone knows the rpm/mp setting for this condition) and with the Hartzell 70" CS prop set at cruise/flat pitch I could only hold about a 1400-1600 fpm descent - at coarse pitch and the same airspeed I was able to descend at about 450 fpm. I think a stopped prop is about halfway between, maybe 700 fpm (?). A dead engine can be dead in at least two ways - still turning (no gas) and stopped/seized (no oil). If it's still turning, it may be possible to pull the prop to coarse pitch, but never to "feather" (darn). If it is stopped, you are left with whatever pitch it is at, probably flat. These situations would seem to indicate 3 entry altitudes for consideration. If a 360 degree circle is required at the standard rate, 3 degrees per second or 2 mins around. At 105 KIAS that is about a 15* bank angle, 3400 foot radius and about 3.5 NM around the arc. Assuming you still have electricity, it should take no more than 10 seconds to lower the gear - this dramatically increases the drag and the rate of descent (I wonder what it goes to). Flaps can be added at your descretion (maybe). Anyway, if your prop is turning in coarse pitch, maybe you can start a few hundred feet above 1000 AGL. If you can't get it to coarse pitch, it looks like somewhere above 3200 feet AGL and if nothing is moving (except for that shaking hand), maybe somewhat above 1500 AGL.
For me, the window is not very large in that most local flying is done at about 3000 feet AGL - not much time to glide to the nearest airport and work this type of entry. I generally fly the downwind (when not doing those straight ins with a steep descent angle) at 1000 AGL and 110 KIAS - of course, this should allow me to get on a runway with a turning engine failure.
Anyone got any suggestions for those mountain crossings with the course line messed up by weather and nothing useful shows up on the moving map set at the 30 mile range?
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Larry,
You answered most of my questions before I asked them (crossing e-mails). It looks like my guesses are a bit on the low side. I will try this next time it's warm outside - hot even - and from higher up.
Scott Krueger
Sky2high@aol.com
II-P N92EX IO320 Aurora, IL (KARR)
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