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Randy,
It is my understanding that best glide on a IV is 120kts (your airplane
might vary) not 120 mph. I use 120kts and rounding out to a
squeaker is not an issue. I would agree with you that 120mph
(104kts) might not leave you with enough energy to arrest the sink
rate.
I have received training from both HPAT and LOBO and my generic engine out
practice goes something like this. Lose the power somewhere on the down
wind (different spots on the down wind provide different "looks"). Pull
the prop (reduces drag) and pitch for 120kts. Turn base at a spot
that, based on the winds, I estimate will allow me to touch down between
1/3 down the runway and mid field. Once I know I can glide to mid
field I drop the gear and add pitch down to still maintain 120kts. If I
need to scrub more altitude I drop flaps as needed, a little at a time because
you can't take'm back, but always pitch for 120kts. This allows for
a normal level off to a normal landing attitude resulting in a landing just
like any other.
Good luck and enjoy your flying.
Ken Kellner
IV-P 14LK
----- Original Message -----
Sent: Tuesday, January 26, 2010 10:10
AM
Subject: Engine out gear down Issue/The
procedure! This was a wake up call for me...
All/ Gary, Good points, The extra 15 - 20 knots is
what you give away dropping gear and flaps transitioning from best glide
profile to landing configuration with a dead engine.
My point is
that when you are done gliding (at 120mph) and ready to touch
down, the extra energy is necessary if you intend to drop gear and flaps
to touchdown . If a landing is being attempted with no gear, 100 or
even 80-90 mph is good to ground effect, bleed off speed and land on the
belly. I am with you there.
If you have your 120 mph glide and
drop the gear at 500 or 1000 feet AGL you are not going to be able to
arrest the decent at the ground. I was shocked to find this
out and almost broke my airplane learning this lesson. It is absolutely
true and it scares me that many, including myself are cruising slow
(100kts) and low (pattern altitude) dragging gear and flaps with partial
power. Loss of power at that poing is much much worse than I and ( I
believe) most of us realize!!!
Before understanding this a
little better, in an engine out situation, I would have set up for
best glide at around 120 mph, find a reasonable spot to land, drop the
gear at 500- 1000 ft AGL and put it down. This works for a Cessna 150 or
172. For a Lancair the first part is right the second is DEADLY
WRONG....Everyone should try this at a very safe altitude. It is
shocking! I had no idea this was the case!!!
Set up best glide at
120 MPH or 106 kts 1000 feet above your imaginary ground level with
absolutely no power (flat idle), descend to 500 ft above your imaginary
ground level and drop the gear (flaps if you like) . You are now slowed
to 85-90 mph dragging the wheels and descending at 1000 feet per minute
or more. Do this to your imaginary ground level, try to flair the
airplane and you blow right through it in a 1000 to 1500 feet per minute
decent!!! No kidding. Try and be aggressive with back elevator to make
it flair and you will stall and could easily turn it over. TRY THIS ONLY
AT A VERY SAFE ALTITUDE! We are so used to a little power on approach
that we really never experience this until a real emergency happens
Remember it is dramatically
worse with a totally dead engine as you have a huge increase in prop
drag.
I believe the procedure should be best glide speed
( I like Gary's 120 MPH) and then pickup the extra 15-20 knots to short
final and drop the gear and flaps and touch down in the last 10 seconds
before the gear/ flap drag bleed off the extra 10 -15 knots. You do not want to fly any longer
than 10 -15 seconds with a dead engine and gear extended. Not
because the airplane wont fly that way, it will. It is because after
those 15-20- extra knots are gone, you can not arrest the decent at the
ground. That was totally foreign to my thinking before this. With the
gear down you can not descend steep enough to pick up enough speed to
flair at the ground. Yikes!
A local Legacy driver and friend
explained what he learned when initially practicing engine out landings
in the Legacy. He started his simulations with 160 kts IAS downwind
in the pattern (gear and flaps up). After 4 attempts pulling the power
and trying to fly different variations of tight patterns dropping gear
and flaps in various places he came to the following conclusion: The
only
way to get his Legacy on the ground safely from a complete engine
failure in the pattern was to IMMEDIATELY turn and dive for the end of
the runway holding around 135 knots and dropping the gear/flaps only at
short final. He said it feels like a very radical move but it is the
only way. He has thousands of hours of HP airplane time and is very
experience in the Legacy. He admitted he grotesquely over estimated the
airplanes ability to make the runway with NO power.
He went on to say that few realize the dramatic flight characteristic
change from low power to no power. You loose the small amount of
thrust and add a TON of drag. Each time he turned sooner and
tighter. He also said he would have bought it if he had to do it for
real had he not practiced it several times to truly understand what it
takes to get it down. The story spooked me enough to prove it was true
in my 235/320 and he is absolutely right.
This is important, our
Lancair's absolutely with not round out at the bottom with no running
engine with gear and flaps down, again unless you have the precious
15-20 knots extra energy used at the very last moments as it goes
quickly with wheels down. You trade that extra energy for the flair No
extra speed no flair...
I believe all high performance airplanes
share this behavior to one degree or another. I also strongly believe
engine out landings can be done successfully if we better understand how
our airplanes fly with a dead engine and execute the right emergency
procedures.
IMHO... Sorry for ranting...
I would very
much like to hear from the LOBO fliers on this subject. I am sure this
has come up in the training.
Randy
Snarr N694RS N235/320
--- On Sun, 1/24/10, Gary
Edwards <gary21sn@hotmail.com> wrote:
From:
Gary Edwards <gary21sn@hotmail.com> Subject: [LML] Re:
Airspeed sensing switch /Auto gear extension / Engine out gear down
Issue! To: lml@lancaironline.net Date: Sunday, January 24, 2010,
4:07 PM
That is good info for everyone.
However, in my 235, 120 MPH is the
best glide speed. That equates to 104 knots.. I do not
want to be going any faster in event of an off field landing, and
most likely, I will leave the gear up in that situation. On a
runway, I would use the gear, but unless it is a long runway, I will
also keep the speed not in excess. Any speed above about 80
MPH results is a bounced landing and significant nose high
attitude with the chance of dragging the rudder, and wasted runway
behind me.
Also, a thought in reference to when to drop the gear. 7 to
10 seconds is fine if the plane still has electrical. But if the
dump valve has to be used, that will not be enough time to get the
gear down, especially if the pilot has to crab the plane one or two
directions to lock each or both mains in place. The pilot is
going to be a "busy beaver" in the last 30 seconds of flight.
Gary Edwards
LNC2
-----
Original Message -----
Sent:
Saturday, January 23, 2010 12:20 PM
Subject:
[LML] Airspeed sensing switch /Auto gear extension / Engine out gear
down Issue!
Terrence, Mine is the same as yours only no
auto gear down. Only a warning light and horn for low speed
and gear up.
I would seriously consider changing your
set up for the following reason. This is a bit of a long
winded response but it brings up a vitally important point for
the group.
Gear and flaps down too early with a
dead engine will have disasterous consequences every
time.
With loss of power, gear and flaps should stay up
keeping speed above 120 kts IAS until the last seconds before
landing. My gear down is a count to 7. Everyone should know
how many seconds it takes to get it down and locked as you
will only have one shot to get it right in an emergency. You
wont' be able to do that with your gear set up.
Many
Lancair drivers (myself included until recently) have no idea
that these how bad these airplanes glide dragging the gear
with a windmilling propeller.
That is a deadly mistake.
Dragging gear and flaps, you need a steep nose down attitude
to keep the airspeed at a safe speed. Unfortunately, in that
regime you can not flair the airplane. When you try to flair
without a little power these airplanes just slow down and hit
the ground. The situation is much worse if you are heavy.
This is very important for every Lancair driver to
understand,
With a dead
engine if the gear and flaps are down too early (anything
sooner than 10 seconds before ground contact) the incident
will most likely have a tragic outcome. This is absolutely
true.
I don't mean to preach but I believe we
would still have some good friends with us if we all
understood this better. We recently had a fatal crash at my
field where an experienced instructor died in a 210 in a
similar circumstance which got me thinking about this.
The ONLY way to get down safely on your wheels in our
airplanes is to keep and extra 15 or 20 KTS of energy (over a
typical approach) all the way to ground effect and then drop
the gear and flaps and bleed off speed and touch down. That
extra energy is used quickly extending the wheels and you will
need to be touching down when it is gone or you are toast
This applies to me as much as anyone else..
Randy
Snarr N694RS
--- On Fri, 1/22/10, Terrence
O'Neill <troneill@charter.net> wrote:
From:
Terrence O'Neill <troneill@charter.net> Subject:
[LML] Re: Airspeed sensing switch needed To:
lml@lancaironline.net Date: Friday, January 22, 2010,
3:08 PM
Thanks for the info, Randy
I have my airspeed sensing switch set a 90 knots, in
the gear-up circuit, so that no matter where the gear switch
is, it can't raise the gear unless the airspeed is greater
than 90 knots.
Same on landing. I fi forget to put the gear
switch to down, the gear will come down anyway at 90
knots.
The only downside (no pun intended) is that should I
want to make a gear-su forced landing, I couldn't... and
have considered adding a bypass into the circuit.
Any thoughts on that/
Terrence
L235/320 N211AL
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