Today's Message Index:
----------------------
1. 04:38 AM - Re: Blanking Effect (Kayberg@AOL.COM)
2. 05:58 AM - Re: Blanking Effect (EAFerguson@aol.com)
3. 06:05 AM - Re: Blanking Effect (N1BZRich@AOL.COM)
4. 10:36 AM - Re: Blanking Effect (Kayberg@AOL.COM)
Message 1
INDEX | Back to Main INDEX |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Blanking Effect |
Buz,
I was suggesting a flaps-up takeoff only. It is easy to rig the plane so
flaps and ailerons are all even. If you take off in that configuration, then
you should not have any serious wing drops. Of course you would then test the
flaps while exploring slowflight and perhaps approaches to stalls. You can
make rigging adjustments later.
It was the comment of some that they "ran out of elevator" on landing and
blamed "blanking". I dont know if that is really the story or not. There are
several possible causes including poor piloting. Sometimes there is a
point in landing a Lightning where you have full back stick, full flaps, nose
up
position and you simply must wait for the touchdown. The nose doesn't pitch
down, which rules out the "blanking". But you can have a sense that you
have no control for a millisecond.
Doug
In a message dated 10/20/2008 8:06:18 P.M. Eastern Daylight Time,
N1BZRich@aol.com writes:
Doug,
I generally agree with your "short answer" comment that the airplane is
not going fast enough to get pitch authority. However, I am not familiar
with "blanking" being suggested (and debated) that had to do with full flaps and
limited elevator just before a stall landing. What are we talking about
here? The basic design of the Lightning (elevator not high above the thrust
line and flaps limited to 40 degrees full down) will prevent any blanking of the
elevator certainly up to and at the stall angle of attack. In fact with
flaps down, you are much further from even getting close to this situation than
you are with flaps up. Remember what the Lightning does as you lower flaps -
the nose goes down. And I have not idea what is meant by "limited
elevators".
I also don't totally agree that the first flight should be with no flaps at
all. For the first flight in a Lightning, during the "near stall
investigation" portion, I recommend you accomplish the yaw, roll, pitch and trim
investigation between speeds of 85 to 65 mph, clean, then at 10 degree flaps,
then
at 20 degrees, and then at 30 degrees. Some people even take the bottom end
of the speed down to 60 mph and that would work well with the new tips and
still keep you above the predicted clean stall speed. Of course if any of these
step by step objectives indicate any problems, stop at that point and make
that first landing at the previous setting. This is kind of what is
recommended in the FAA Advisory Circular 90-89 (I hope I am remembering that
number
right.)
Buz
Message 2
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Blanking Effect |
In a message dated 10/20/2008 8:37:58 P.M. Eastern Daylight Time,
ryan@greenlandings.com writes:
Walt,
If I am not mistaken your aircraft is at Greg Hobbs airport.
Walt. Having visited Greg's place (~1000' runway with fences at both ends) I
would expect the first test flight to be made with at least 10 deg flaps. If
the runway is rough, as it was when I was there, any perceived loss on
elevator authority would call for an immediate abort. One suggestion would be
to
truck it over to a local paved and longer runway like Marana. Not simple or
cheap, but it would provide a better setting for testing.
With 250+ hours and about that many take offs and landings in my Lightning,
I've never had any indication of blanking. I do most TOs no flap, but have
been through the full flap deployment range to test. I frequently side slip to
lose alt on landing, but don't think I've ever had full rudder in doing it.
Never a hint of loss of elevator authority.
One possibility that has not been mentioned is to check the horizontal stab
incidence. If incorrect by even a small amount, this could be the problem.
Finally, the trim system makes a difference. You will have more elevator
authority with the servo trim than with the bungee. That comment will probably
start a new discussion thread, but trust me. We changed to the new system on
N17EF at 200+/- hours and there is a definite difference. "We" was mostly Nick,
I was there to watch. Since your's is a newly completed ship, it probably
has the new trim system, but I haven't seen that stated in the e-mails.
Hope these comments help.
Earl Ferguson
**************New MapQuest Local shows what's happening at your destination.
Dining, Movies, Events, News & more. Try it out
(http://local.mapquest.com/?ncid=emlcntnew00000002)
Message 3
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Blanking Effect |
In a message dated 10/21/2008 7:39:09 A.M. Eastern Daylight Time,
Kayberg@AOL.COM writes:
Sometimes there is a point in landing a Lightning where you have full back
stick, full flaps, nose up position and you simply must wait for the
touchdown. The nose doesn't pitch down, which rules out the "blanking". But
you can
have a sense that you have no control for a millisecond.
Doug,
Right on. Just substitute the word Lightning for airplane and it sounds
like the perfect set up for a full stall landing. The millisecond or
whatever time delay will depend on just how high you flared above the runway.
Hopefully six inches or so.
Buz
**************New MapQuest Local shows what's happening at your destination.
Dining, Movies, Events, News & more. Try it out
(http://local.mapquest.com/?ncid=emlcntnew00000002)
Message 4
INDEX | Back to Main INDEX |
PREVIOUS | Skip to PREVIOUS Message |
NEXT | Skip to NEXT Message |
LIST | Reply to LIST Regarding this Message |
SENDER | Reply to SENDER Regarding this Message |
|
Subject: | Re: Blanking Effect |
Few things in life compare to that feeling when you realize you are in full
stall about 10 feet above a runway....when you thought it was 10 inches!
Thankfully a Lightning will float in better than many others if you just wait.
Of course power will help, but that feeling is priceless!
Doug
In a message dated 10/21/2008 9:06:05 A.M. Eastern Daylight Time,
N1BZRich@AOL.COM writes:
In a message dated 10/21/2008 7:39:09 A.M. Eastern Daylight Time,
Kayberg@AOL.COM writes:
Sometimes there is a point in landing a Lightning where you have full back
stick, full flaps, nose up position and you simply must wait for the
touchdown. The nose doesn't pitch down, which rules out the "blanking". But
you can
have a sense that you have no control for a millisecond.
Doug,
Right on. Just substitute the word Lightning for airplane and it sounds
like the perfect set up for a full stall landing. The millisecond or
whatever time delay will depend on just how high you flared above the runway.
Hopefully six inches or so.
Buz
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|