Return-Path: Sender: (Marvin Kaye) To: lml@lancaironline.net Date: Fri, 04 Jun 2004 14:29:45 -0400 Message-ID: X-Original-Return-Path: Received: from audiogram.mail.pas.earthlink.net ([207.217.120.253] verified) by logan.com (CommuniGate Pro SMTP 4.2b4) with ESMTP id 130062 for lml@lancaironline.net; Fri, 04 Jun 2004 13:26:03 -0400 Received: from lsanca1-ar17-4-61-192-044.lsanca1.elnk.dsl.genuity.net ([4.61.192.44] helo=skipslater) by audiogram.mail.pas.earthlink.net with asmtp (Exim 3.36 #4) id 1BWIRg-0003o2-00 for lml@lancaironline.net; Fri, 04 Jun 2004 10:25:32 -0700 X-Original-Message-ID: <001501c44a59$2ec31c60$6401a8c0@earthlink.net> Reply-To: "Skip Slater" From: "Skip Slater" X-Original-To: "Lancair Mailing List" References: Subject: Re: [LML] Unsafe in any plane X-Original-Date: Fri, 4 Jun 2004 10:27:11 -0700 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0012_01C44A1E.7F588B00" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 X-ELNK-Trace: cbee950bdf563876c8ad50643b1069f8239a348a220c2609223ab545e93cb3aeec84de5239472f92548b785378294e88350badd9bab72f9c350badd9bab72f9c This is a multi-part message in MIME format. ------=_NextPart_000_0012_01C44A1E.7F588B00 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Some random thoughts on spin recoveries: My up front disclaimer is that I am not a IV/IV-P flyer, have no = significant level of expertise in the plane and my comments are generic = in nature to hopefully give some food for thought. As a former military = pilot, I have a fair amount of experience spinning airplanes, both props = and jets. While I've been surprised by some of the spin entries and = exits, the ratio of the two is 1:1 for me, so in that regard I have been = successful in dealing with them. =20 I'd also like to note that I've never entered a spin unintentionally and = that I've also never attempted one where I wasn't either wearing a = parachute in a plane designed for easy egress or sitting on an ejection = seat. I have no intention of ever exploring that part of the flight = envelope in my ES regardless of my experience. In the case of the IV-P, there are a few knowns from my own observations = and what I've learned from about five years reading the LML: 1. When Dave Allen, acting as a professional test pilot for an ES = builder, entered an unintentional spin at a mid CG location, he observed = that he didn't believe the ES has enough elevator or rudder to recover = from a spin at an aft CG. The IV's have a much smaller horizontal stab = and elevator than the ES, which would make recovery even more = problematic. =20 2. The ES's typically have an empty CG that's near or right at the = forward limit and they're nearly impossible to load such that the aft CG = limit is exceeded. The IV's have a more aft CG to start with, which = moves even further aft when the gear is raised. Has anyone ever = measured the CG shift with the gear up? My guess is that some aft limit = loaded planes may actually go out of limits when they raise the gear. 3. It's a fact of life that the further aft the CG is in just about any = plane I can think of, the more difficult it it becomes to recover from a = spin. It occurs to me that anything you could do to move the CG forward = would somewhat enhance your chances of recovery from a spin if you have = sufficient altitude to attempt a recovery, as it appears that the IV-P = over the Grand Canyon had. With that in mind, have any of the = experienced IV flyers/instructors ever suggested dropping the gear to = help move the CG forward in the event of a spin? 4. On the aerodynamic side, a further aft center of lift on the wing = will help get the nose lower. Lowering flaps moves the center of lift = aft. Has there ever been any suggestion to partially lower the flaps on = the IV's in the event of a spin to help lower the nose (and angle of = attack)? Worrying about a possible flap overstress seems to be a moot = point when lives are at stake.=20 5. We all know that the p factor from our props gives a push to the = left side of the vertical stab, necessitating varying degrees of right = rudder to counter it. If you happen to enter a spin that's turning to = the RIGHT, using power would seem to me to offer some additional = aerodynamic help in stopping the rotation. CAUTION: There's the very = real possibility that a recovery of this nature could rapidly develop = into a spin in the opposite direction if the controls aren't neutralized = and power pulled to idle at the first sign of recovery, so a pilot would = have to be spring loaded to recognize a recovery. There's no substitute for training and you can't train for spins an any = Lancair. There's a huge difference between a reasoned, experienced = reaction to a stall, post stall gyration, departure or a fully developed = spin and a reaction of stark terror and panic because you find yourself = in a situation you've never seen before. We can talk all we want about = proper training in Lancairs, but unless you've had military experience = with all of this stuff, proper high performance training for us as = pilots should include spin training at an established aerobatic school. = It's a small investmment that will increase not only our awareness of = the elements of a spin, but avoidance of them and the proper recovery = from them. While that won't guarantee that you'll be able to recover an = aft loaded IV-P or any other plane for that matter (altitude most often = being the limiting factor for recovery), it will certainly offer us the = best chance at it. I welcome the comments of our experienced IV drivers and teachers out = there. Skip Slater N540ES =20 ------=_NextPart_000_0012_01C44A1E.7F588B00 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Some random thoughts on spin=20 recoveries:
 
My up front disclaimer is that I am not = a IV/IV-P=20 flyer, have no significant level of expertise in the plane and my = comments are=20 generic in nature to hopefully give some food for thought.  As a = former=20 military pilot, I have a fair amount of experience spinning airplanes, = both=20 props and jets.  While I've been surprised by some of the spin = entries and=20 exits, the ratio of the two is 1:1 for me, so in that regard I have been = successful in dealing with them. 
 
I'd also like to note that I've = never entered=20 a spin unintentionally and that I've also never attempted one where I = wasn't=20 either wearing a parachute in a plane designed for easy egress or = sitting on an=20 ejection seat.  I have no intention of ever exploring that part of = the=20 flight envelope in my ES regardless of my experience.
 
In the case of the IV-P, there are = a few=20 knowns from my own observations and what I've learned from about five = years=20 reading the LML:
 
1.  When Dave Allen, acting = as a=20 professional test pilot for an ES builder, entered an unintentional = spin at=20 a mid CG location, he observed that he didn't believe the ES has enough = elevator=20 or rudder to recover from a spin at an aft CG.  The IV's have a = much=20 smaller horizontal stab and elevator than the ES, which would make = recovery even=20 more problematic.  
 
2.  The ES's typically have an = empty CG that's=20 near or right at the forward limit and they're nearly impossible to = load=20 such that the aft CG limit is exceeded.  The IV's have = a more aft=20 CG to start with, which moves even further aft when the gear is = raised. =20 Has anyone ever measured the CG shift with the gear up?  My guess = is that=20 some aft limit loaded planes may actually go out of limits when = they raise=20 the gear.
 
3.  It's a fact of life that the = further aft=20 the CG is in just about any plane I can think of, the more difficult = it it=20 becomes to recover from a spin.  It occurs to me that anything = you=20 could do to move the CG forward would somewhat enhance your chances of = recovery=20 from a spin if you have sufficient altitude to attempt a recovery, as it = appears=20 that the IV-P over the Grand Canyon had.  With that in mind, have = any of=20 the experienced IV flyers/instructors ever suggested dropping the = gear to=20 help move the CG forward in the event of a spin?
 
4.  On the aerodynamic side, a = further aft=20 center of lift on the wing will help get the nose lower.  = Lowering=20 flaps moves the center of lift aft.  Has there ever been any = suggestion to=20 partially lower the flaps on the IV's in the event of a spin to help = lower the=20 nose (and angle of attack)?  Worrying about a possible flap = overstress=20 seems to be a moot point when lives are at stake. 
 
5.  We all know that the p factor = from our=20 props gives a push to the left side of the vertical stab, necessitating = varying=20 degrees of right rudder to counter it.  If you happen to enter a = spin=20 that's turning to the RIGHT, using power would seem to me to offer some=20 additional aerodynamic help in stopping the rotation.  CAUTION: = There's the=20 very real possibility that a recovery of this nature could rapidly = develop into=20 a spin in the opposite direction if the controls aren't neutralized = and=20 power pulled to idle at the first sign of recovery, so a pilot would = have to be=20 spring loaded to recognize a recovery.
 
There's no substitute for training and = you can't=20 train for spins an any Lancair.  There's a huge difference between = a=20 reasoned, experienced reaction to a stall, post stall gyration, = departure=20 or a fully developed spin and a reaction of stark terror and panic = because you=20 find yourself in a situation you've never seen before.  We can talk = all we=20 want about proper training in Lancairs, but unless you've had military=20 experience with all of this stuff, proper high performance training for = us as=20 pilots should include spin training at an established aerobatic=20 school.  It's a small investmment that will increase not only our = awareness=20 of the elements of a spin, but avoidance of them and the proper recovery = from=20 them.  While that won't guarantee that you'll be able to recover an = aft=20 loaded IV-P or any other plane for that matter (altitude most often = being the=20 limiting factor for recovery), it will certainly offer us the best = chance at=20 it.
 
I welcome the comments of our = experienced IV=20 drivers and teachers out there.
 
Skip Slater
N540ES
 
    =20
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