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I find that most people seem to be happy with emphirical results and don't
do anything about details while others pursue the actual facts and details,
sometimes bordering on OCD.
I'm in the second group. Even after I see what, I still look
for how. and why.
Wolfgang
----- Original Message -----
Sent: Tuesday, August 20, 2013 7:41
AM
Subject: Re: [LML] Re: Fw: [LML] Re: FW:
[LML] Flaps on take-off?
Wolfgang,
The constant speed prop log book will detail the
manufacturer's pitch limits (blade angle stops) - for the Hartzell
2-blade 70" prop used by 320's that was 12 and 40 degrees (or 45 as I don't
have the prop log anymore, someone can just look at their log and report
back).
The line for the C172 was arbitrary and used in a discussion about
the proportional effect of drag on a slick airplane and one already
inherently draggy.
Stop arguing from the sidelines and go try it.
Scott Krueger
In a message dated 8/19/2013 11:40:30 A.M. Central Daylight Time,
Wolfgang@MiCom.net writes:
Where did the 320 and 172 information come from ?
Fixed pitch props will continue to windmill but what about constant
speed ? - - I haven't tried this with a non-responsive, non seized
engine.
The next question is what is the blade angle, resulting from a wind
driven constant speed propeller, for the "max" rpm and "min" rpm lever
positions.
The control loop gain will be "adverse" in that scenario (wind
driven vs shaft driven).
. . . in the wind driven mode - as the rpm decreases - the pitch
is made to go flatter - making the rpm decrease more - - -
After consulting with H&S Prop Shop here in Michigan, the light
goes on.
It does not matter where the RPM lever is set.
With a non-responsive engine, the blades will go to the minimum pitch
set by the physical stop in the prop hub,
. . . typically 10-15 degrees depending on setup for the particular
installation.
Now a feathering prop is a different ball game . . .
Wolfgang
----- Original Message -----
Sent: Sunday, August 18, 2013 10:53
AM
Subject: Re: [LML] Fw: [LML] Re: FW:
[LML] Flaps on take-off?
Wolfgang,
See the diagram for drag from wind milling and fixed prop.
Hartzell CS prop for 320 flat pitch is 12 and coarse is 40 degrees.
Base diagram from Aeronautics for Naval Aviators.
Scott Krueger
In a message dated 8/18/2013 9:45:25 A.M. Central Daylight Time, Wolfgang@MiCom.net writes:
But . . . when you added power, didn't you
also increase the prop rpm ?
Makes me wonder . . . in gliders we
modulate drag with spoilers . . . how much drag off the propeller disk
can be modulated by using the prop rpm control ?
. . . but then again . . . if the engine is
ceased . . . the spring in the prop hub makes the blades go flat pitch .
. . maximum drag !
Wolfgang
----- Original Message -----
Sent: Thursday, August 15, 2013
9:39 PM
Subject: RE: [LML] Re: FW: [LML]
Flaps on take-off?
Robert,
I suppose you
could run out of gas, but I think the reason for the exercise was to
teach the pilot how far the plane would glide with power off in case
he was trying to make a farmers field in a real
emergency.
I think you
would be surprised about the feathered prop. I was trying to
change my landing technique the other day by changing the prop to a
coarse setting while in the pattern and locking it in that
setting. I had to give it up because when the plane got into
ground effect, it just glided the entire length of the runway and
would not stop flying! Then when I added power to do a go
around, the plane didn’t want to fly because of the lack of power from
the coarse prop.
I was trying
this because I didn’t think I liked the fact that the plane would slow
down so fast with the prop in fine pitch when I pulled the power
back. I have now decided that I like it fine!
:>)
B2
From:
Lancair Mailing List
[mailto:lml@lancaironline.net] On
Behalf Of Lancair-ESP
Sent: Thursday, August 15, 2013
6:25 PM
To:
lml@lancaironline.net
Subject: [LML] Re: FW: [LML]
Flaps on take-off?
Bill,
What you
describe is certainly a possible scenario – actually that sounds like
my typical arrival. With the engine pulled back to 10-12” and a
windmilling prop the decent rate should be similar zero power and a
feathered prop.
But how
likely is an engine that fails in the close pattern after a
cross-country flight? More likely something would go afoul
enroute, when the pilot could select a landing spot and arrive 2000 ft
above it. If not able to arrive 2000 ft agl – choose an
alternate spot.
Just my
couple lira . . .
Robert
From:
Bill Bradburry [mailto:bbradburry@bellsouth.net]
Sent: Wednesday, August 14, 2013
2:06 PM
To:
lml@lancaironline.net
Subject: RE: [LML] FW: [LML]
Flaps on take-off?
Robert,
You should
try it under conditions that are more likely to be the case.
Descend to
pattern altitude, 1000 ft AGL, slow to pattern speed, and idle the
engine abeam the numbers and see if you can make
it
I recommend
you idle the engine and not kill it, because I would be surprised if
you do make it. I also don’t recommend you coarse pitch the prop
since you may need to add power for the go
around.
Bill
Bill,
I
practiced that maneuver with a Lancair company pilot flying my ES-P
and found it a non-event.
Overhead
upwind at 2000 ft agl and slowing to pattern speed in the
turn.
No flaps
until over the fence then deployed everything and aimed for 1/3 down
the runway.
I
realize the IV would take different speeds but it should still be
do-able with a little practice.
Robert
ES-P
N301ES
That seems a
scenario where you would be in better shape with the flaps up.
You very well might make the runway. With flaps down, you likely
would not and it would be very dangerous to try and retract
them. With the high wing loading that all the Lancairs have,
they are flying bricks with no power. I think almost nobody
makes the approach to land with no power.
Remember way
back in primary training when the instructor had you remove power
abeam the numbers and make the landing without having to add
power? Does anyone practice that maneuver with their
Lancair?
Bill
B
Matt, I
agree with the others that w's insults are inexcusable, but I must ask
a question.
What do you do if your low over
the departure end of the runway and the engine
quits?
1. Land at high speed
flaps up.
2. Lower the flaps
and deal with the big trim and pitch change while making all the other
decisions and actions required in
parallel.
----- Forwarded Message
-----
From: "marv@lancair.net" <marv@lancair.net>
To: lml <lml>
Sent: Monday, August 12, 2013
4:02 PM
Subject:
[LML] Re: Flaps on take-off?
Posted
for Matt losangeles <mattinlosangeles@yahoo.com>:
>
I feel much safer adding 5 knots or so on the ground before I lift off
so I
>don't have to mess with trim when I am low to the ground.
I could see a
>scenario where I take off IFR and I am
immediately handed off to departure
>control while I am putting
the flaps up. They tell me to do something the
>requires me to
look at my map and the next thing you know, while distracted,
> I am at an unusual attitude really close to the ground.
When I am down low
>like that I want to make sure if I am
distracted it isn't a problem, the
>plane just keeps on
climbing along at Vy or so.
>
> I also would guess
if you use flaps on take off, this adds drag and slows
>your rate of climb (I have not tested this). I am able to
be at Vy a couple
>seconds after take off and I am going to get
to a safer altitude before the
>guy using flaps (again, this is
my guess since I have not tested the two
>scenarios).
>
> Another thing. It is an experimental aircraft. As it
states on the
>EAA, "There is no FAA approved
flight manual or POH for experimental
>aircraft, nor is there
a TC".
>
> Ohh, what about those
reno
racer Legacy aircraft that have just bonded thier
>flaps in
place so they can't go down in order to eliminate the drag of the
>hindges. I guess they are not flying those aircraft the way
they were meant
>to be flown. You could argue they are
reno
racers I suppose. It is also
>likely they are using those
planes the other 51 weeks out of the year to fly
>all over the
place and those planes don't seem to be crashing on takeoff.
>
> "I believe everyone would agree that flaps do add a
margin of safety"
> I personally consider myself part of
everyone and I don't agree that flaps
>do in fact add a margin
of safety on take off. I use them on landing so I can
>see out
the window and out of habit I suppose. If the speed you land at
makes
>such a difference, then the best thing to be doing is
flying a plane that
>lands at a slower speed.
>
> Perhaps if we were all 100 hour pilots, blindly
following the POH makes
>sense. It is funny, I remember having
this EXACT same argument on a Mooney
>board. I used to take off
without flaps when I had a Mooney and I heard the
>same thing
there. Follow the POH explicitly or you are completely reckless
>and should have your license taken away. At least those Mooney
guys had a
>point. That was a certified aircraft with a POH
that said to take off with
>flaps.
>
>
Something else to consider, if flaps are so critical to flight on our
>planes, why on earth don't they have a back up system to
ensure they always
>go down when needed like our landing gear
has? My guess is because the plane
>will fly just fine without
them.
>
> Matt
>
>
>
________________________________
> From: Art Jensen <flycassutts@yahoo.com>
>
To: lml@lancaironline.net
>
Sent: Monday, August 12, 2013 1:46 PM
> Subject: [LML] Re: To
Marv
>
> Maybe Wolfgang was short on political
correctness, but the truth remains
>that if you cannot or do
not fly the plane as it was meant to be flown then
>you should
not be flying that plane.
>
> I believe everyone would
agree that flaps do add a margin of safety and
>should be used
for take-off and landing as per your POH and I believe every
>instructor giving training in a Lancair would
agree. If an instructor
>reading this disagrees,
please share why you disagree with me.
>
> Art
>
> Sent from Yahoo! Mail for iPad
>
>
> ________________________________
>
From: steve <n5276j@aol.com>; To: <lml@lancaironline.net>; Subject:
> [LML] Re: To Marv Sent: Mon, Aug 12,
2013 5:39:28 PM
> I second your post. I
am surprised by the comment.
>
> steve
alderman N25SA 360
>
> .
>
-----Original Message----- From: Claudette Colwell <colwell.ch@gmail.com>
>To: lml <lml@lancaironline.net>
Sent: Mon, Aug 12, 2013 5:43 am Subject:
>[LML] To
Marv
> It is very regretful the comment from
Wolfgang apparently directed to Matt
>appeared on the
LML. This has always been a constructive exchange of
>information and ideas. That type of personal comment is
not in keeping with
>the spirit of cooperative sharing of
information.
>
>
Claudette
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