X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 01 Feb 2010 11:40:20 -0500 Message-ID: X-Original-Return-Path: Received: from web111404.mail.gq1.yahoo.com ([67.195.15.150] verified) by logan.com (CommuniGate Pro SMTP 5.3.2) with SMTP id 4106334 for lml@lancaironline.net; Mon, 01 Feb 2010 01:38:29 -0500 Received-SPF: none receiver=logan.com; client-ip=67.195.15.150; envelope-from=randylsnarr@yahoo.com Received: (qmail 77820 invoked by uid 60001); 1 Feb 2010 06:37:54 -0000 DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Message-ID:X-YMail-OSG:Received:X-Mailer:Date:From:Subject:To:Cc:In-Reply-To:MIME-Version:Content-Type; b=XBPJjklBPtniGiUqR91HGMX6gIwIa10zptU7L75hEEPvpADls0eL+R6lY23np8QCZ8+i86L0fr8Gy+46B8DEoeV0cqUesVg6BInUa149IE25ZQ9In9jQpjm4lwMZmsych1ivpjqjjLGJ5IcVUZchW9v96qgPrtXm67hNeq/eKxU=; X-Original-Message-ID: <117225.77530.qm@web111404.mail.gq1.yahoo.com> X-YMail-OSG: 4gHXhGwVM1k.iwQodVfWiseGtnSIGrXjiudgV5g7xEhEhcPHF89Ho86ygkz0VppIMcc_4_dQQLdh4FsKDQP6jA5M4Tj5s4e.ZBkMQIexqD.3VwgBzB3ds6VXwpgmm6S9py7kBQGEu61VEbVnyRYdfq2tECILpx.y2JDkPxyGVUtt6GN7_wMyZa8_fjX2rbuqrmxkbsyXKJm74Lg.zu7iMHnP305_Vamyw__mK8IhgPJ6FQpIQMUPIVats5JEpIjDuFWhi2rMbFsZjUNwDUuyCPzChGrJFazAS.qsId5Wv0xeKyqTQxkCmxXGs0lnJA9.MAw5saxaTYCpChcH1TsR4sztLtv5njBW7HCvkdC1jn.YUUtrjSTJtKPGjkiA9NDkJQ-- Received: from [76.8.220.18] by web111404.mail.gq1.yahoo.com via HTTP; Sun, 31 Jan 2010 22:37:53 PST X-Mailer: YahooMailClassic/9.1.10 YahooMailWebService/0.8.100.260964 X-Original-Date: Sun, 31 Jan 2010 22:37:53 -0800 (PST) From: randy snarr Subject: Re: [LML] Re: Engine out gear down Issue/The procedure! This was a wake up call for me.. X-Original-To: Lancair Mailing List X-Original-Cc: Mark Patey In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="0-137306449-1265006273=:77530" --0-137306449-1265006273=:77530 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Bill, I am also doing my testing at 4500 ft elevation which is going to be differ= ent than near sea level where you live. But, what could be the harm in 10-15 extra knots in the last moments of a d= ead stick landing? We all know you can bleed that off before touch down. Better 10 knots too m= uch than 1 knot not enough. I have yet to hear of anyone that has landed de= adstick too fast and run off the end of the runway in an LNC2 or any other = airplane for that matter. Everyone is short. Everyone! That means everyone = is making the same mistake to varying degrees which is the point I am tryin= g to make. The fatals are all in the not enough knots category usually turning over cl= ose to the ground... Usually Short... This is obviously pure speculation but I believe 100 % of the low altitude = stall spin victims (some of which were experienced pilots) would gladly tak= e the extra 10- 15kts reserve energy and keep it as long as possible if the= y had a second chance to perform the maneuver. This is true in my airplane and my friend in the Legacy has proved this poi= nt in his. It took him 5 or 6 attempts to finally get the procedure down ri= ght. Even with his experience, he was shocked that such an aggressive move = ( diving for the 1st third of the runway,15 knots extra speed and very late= with the gear and flaps/ bleed the speed to touch down) was needed to get = the airplane down successfuly. He has no doubt he would have badly over est= imated his ability to make the runway and would have certainly landed tragi= cally in the not enough knots group. I believe several of our friends have = tragically discovered this when they attempted it for the first time for re= al.=20 I am no expert and I don't claim to be one in real life or on TV. My partin= g thought is to do what the other high performance drivers do (TBM, Pilatus= ect)=A0 1500 foot patterns, a little extra energy to land because airspeed= energy leaves our craft (especially dead stick and dirty) DRAMATICALLY mor= e than manyt of us realize. Myself included... IMHO Randy Snarr N694RS 235/320 --- On Sun, 1/31/10, Bill Kennedy wrote: From: Bill Kennedy Subject: [LML] Re: Engine out gear down Issue/The procedure! This was a wak= e up call for me.. To: lml@lancaironline.net Date: Sunday, January 31, 2010, 9:58 PM Math is nice but if you don't practice this stuff you're probably going to = die if you have an engine failure. Also, this stuff about needing 120kias t= o round out in a Lancair is dead wrong as is the notion of lowering your ge= ar at the last minute. What is hpat teaching? Sent from my iPhone On Jan 31, 2010, at 6:57, Gary Casey wrote: I ran through some numbers regarding Michael's comments below. =A0Starting = with the sailplane comment, he says that slowing from 135kts to 65 in a zoo= m can result in a gain of 800 feet. =A0If all the energy were converted to = altitude(no drag) the gain would be 1,276 ft, so a gain of 800 ft seems rea= sonable for a very low-drag airframe - 2/3 of the energy can be converted t= o altitude. =A0In the case mentioned of 120 kts to 75 kts the number comes = out to a gain of 765 ft. =A0How much of that is eaten up by drag? =A0Certai= nly compared to the sailplane, a lot. =A0Would the altitude gain be half? = =A0I doubt it. =A01/4? =A0Maybe, so as a guess you could count on perhaps a= 200 ft altitude gain. =A0How much do you need to flare? =A0Depends on the = descent rate.=0A =A0I calculated it based on 2,000 ft/min - arresting that = is equivalent to an altitude gain of 34.5 ft, much lower than the 200 ft me= ntioned above. =A0It would be good if someone measured the actual no-power = descent rate with gear and flaps down. In summary, the math suggests that a no-power approach speed of 120 kts sho= uld leave more than enough energy to flare. =A0How much more? =A0I'll bet n= ot a lot, but still more. =A0I don't have an answer to the question, but th= is is how the numbers work out. =A0I have done a full-flap no-power descent= with my ES (gear down, of course :-) at 105 kts and the descent rate was o= ver 2,000 ft/min with a frighteningly high negative deck angle. =A0Flaring = from that condition would be interesting, to say the least. =A0My conclusio= n is that Randy's warning is well founded. I would, perhaps, disagree with the admonition that retracting flaps when o= n=0A final will result in a guaranteed disaster. =A0Certainly any change in= configuration at the last second creates a high work load, but at least in= my airplane, the difference in behavior between 20 degrees and 40 degrees = of flaps is 90% drag. =A0So, if one were to think he was high for the landi= ng, added full flaps and then discovered he was now low, I see no problem w= ith then retracting the flaps to 10 or 20 degrees. =A0Assuming the speed we= re high (120?) the flaps could even be retracted all the way without proble= m except for the pitch change required. =A0And then dropping the flaps duri= ng the flare is a good way to arrest the descent. =A0I'm a little reluctant= to post this last paragraph as I have no credentials (no military fighter = jet experience, no instructor rating, no multi-engine jet time, and no stay= s in Holiday Inn Express) except for a modest understanding of the engineer= ing principles=0A involved. Gary From: Michael Newman Subject: [LML] Re: Engine out gear down Issue/The procedure! This was a wak= e up call for me... To: lml@lancaironline.net Date: Wednesday, January 27, 2010, 4:52 PM I am a LOBO instructor. I own and fly a Lancair IV-P.I am also a sailplane = instructor.=A0This discussion reminds me of one in the sailplane community = talking about deploying full spoilers and being able to flare properly. It = was thoroughly debunked there as it should be here.=A0The issue is carrying= enough energy in the form of airspeed to arrest the rate of descent withou= t going below the stall speed.=A0There is no=0A question in my mind that th= e IV-P with gear down, flaps down, engine stopped and spoilers fully extend= ed can carry enough energy to arrest the rate of descent (flare). 120 knots= will be more than enough. I have landed my IV-P with full spoilers, gear a= nd flaps down. 95 knots is plenty of airspeed to arrest the descent in this= configuration with the engine as pulled back as I can get it.=A0 I doubt a= truly dead engine will add as much more drag as the full spoilers.=A0Glidi= ng at 120 knots=0A with a stall speed is in the range of 75 knots is a diff= erential of 45 knots. This is enough to climb a few hundred feet much less = arrest the rate of descent. Work out the physics and you can see how much a= ltitude you gain for converting this much horizontal speed to vertical spee= d. In sailplanes we expect about an=A0 800 foot altitude gain in a pull up = from 135 knots to 60 knots. Possibly a =A0surprise to people here is that a= Lancair will not be much different. It is energy conversion not drag that = matters.=0A=0A=0A=0A =0A=0A =0A=0A=0A --0-137306449-1265006273=:77530 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
Bill,
I am also doing my testing at 4500 f= t elevation which is going to be different than near sea level where you li= ve.
But, what could be the harm in 10-15 extra knots in the last moments= of a dead stick landing?
We all know you can bleed that off before touc= h down. Better 10 knots too much than 1 knot not enough. I have yet to hear= of anyone that has landed deadstick too fast and run off the end of the ru= nway in an LNC2 or any other airplane for that matter. Everyone is short. E= veryone! That means everyone is making the same mistake to varying degrees = which is the point I am trying to make.
The fatals are all in the not en= ough knots category usually turning over close to the ground...
Usually = Short...

This is obviously pure speculation but I believe 100 % of t= he low altitude stall spin victims (some of which were experienced pilots) would gladly take the extra 10- 15kts reserve energy and keep it as long a= s possible if they had a second chance to perform the maneuver.

This= is true in my airplane and my friend in the Legacy has proved this point i= n his. It took him 5 or 6 attempts to finally get the procedure down right.= Even with his experience, he was shocked that such an aggressive move ( di= ving for the 1st third of the runway,15 knots extra speed and very late wit= h the gear and flaps/ bleed the speed to touch down) was needed to get the = airplane down successfuly. He has no doubt he would have badly over estimated hi= s ability to make the runway and would have certainly landed tragically in = the not enough knots group. I believe several of our friends have tragicall= y discovered this when they attempted it for the first time for real.
<= br>I am no expert and I don't claim to be one in real life or on TV. My parting thought is to do what the other high performance drivers do (TB= M, Pilatus ect)  1500 foot patterns, a little extra energy to land bec= ause airspeed energy leaves our craft (especially dead stick and dirty) DRA= MATICALLY more than manyt of us realize.
Myself included...

IMHO<= br>Randy Snarr
N694RS
235/320

--- On Sun, 1/31/10, Bill Ken= nedy <bill_kennedy_3@hotmail.com> wrote:

From: Bill Kennedy <bill_kennedy_3@hotmail.com>
Sub= ject: [LML] Re: Engine out gear down Issue/The procedure! This was a wake u= p call for me..
To: lml@lancaironline.net
Date: Sunday, January 31, 2= 010, 9:58 PM

Math is nice but if you = don't practice this stuff you're probably going to die if you have an engin= e failure. Also, this stuff about needing 120kias to round out in a Lancair is dead wrong as is the notion of lowering your gear at the last m= inute. What is hpat teaching?

Sent from my iPhone

On J= an 31, 2010, at 6:57, Gary Casey <casey.gary@yahoo.com> wrote:

I ran through some numbers reg= arding Michael's comments below.  Starting with the sailplane comment,= he says that slowing from 135kts to 65 in a zoom can result in a gain of 8= 00 feet.  If all the energy were converted to altitude(no drag) the ga= in would be 1,276 ft, so a gain of 800 ft seems reasonable for a very low-d= rag airframe - 2/3 of the energy can be converted to altitude.  In the= case mentioned of 120 kts to 75 kts the number comes out to a gain of 765 = ft.  How much of that is eaten up by drag?  Certainly compared to th= e sailplane, a lot.  Would the altitude gain be half?  I doubt it= .  1/4?  Maybe, so as a guess you could count on perhaps a 200 ft= altitude gain.  How much do you need to flare?  Depends on the d= escent rate.=0A  I calculated it based on 2,000 ft/min - arresting tha= t is equivalent to an altitude gain of 34.5 ft, much lower than the 200 ft = mentioned above.  It would be good if someone measured the actual no-p= ower descent rate with gear and flaps down.

In sum= mary, the math suggests that a no-power approach speed of 120 kts should le= ave more than enough energy to flare.  How much more?  I'll bet n= ot a lot, but still more.  I don't have an answer to the question, but= this is how the numbers work out.  I have done a full-flap no-power d= escent with my ES (gear down, of course :-) at 105 kts and the descent rate= was over 2,000 ft/min with a frighteningly high negative deck angle.  = ;Flaring from that condition would be interesting, to say the least.  = My conclusion is that Randy's warning is well founded.

=
I would, perhaps, disagree with the admonition that retracting flaps w= hen on=0A final will result in a guaranteed disaster.  Certainly any c= hange in configuration at the last second creates a high work load, but at = least in my airplane, the difference in behavior between 20 degrees and 40 = degrees of flaps is 90% drag.  So, if one were to think he was high fo= r the landing, added full flaps and then discovered he was now low, I see n= o problem with then retracting the flaps to 10 or 20 degrees.  Assumin= g the speed were high (120?) the flaps could even be retracted all the way = without problem except for the pitch change required.  And then droppi= ng the flaps during the flare is a good way to arrest the descent.  I'= m a little reluctant to post this last paragraph as I have no credentials (= no military fighter jet experience, no instructor rating, no multi-engine j= et time, and no stays in Holiday Inn Express) except for a modest understan= ding of the engineering principles=0A involved.

Ga= ry

From: Michael Newman <mnewman@dragonnorth.com>
Subject: [LML] Re: Engine= out gear down Issue/The procedure! This was a wake up call for me...
To= : lml@lancaironline.net
Date: Wedne= sday, January 27, 2010, 4:52 PM

I am a LOBO instructor. I own and= fly a Lancair IV-P.

I am also a sailplane = instructor.

 

This discussion reminds me of one in the sailplane community talkin= g about deploying full spoilers and being able to flare properly. It was th= oroughly debunked there as it should be here.

 <= /p>

The issue is carrying enough energy in the form of= airspeed to arrest the rate of descent without going below the stall speed= .

 

Th= ere is no=0A question in my mind that the IV-P with gear down, flaps down, = engine stopped and spoilers fully extended can carry enough energy to arres= t the rate of descent (flare). 120 knots will be more than enough. I have l= anded my IV-P with full spoilers, gear and flaps down. 95 knots is plenty o= f airspeed to arrest the descent in this configuration with the engine as p= ulled back as I can get it.  I doubt a truly dead engine will add as m= uch more drag as the full spoilers.

 =

Gliding at 120 knots=0A with a stall speed= is in the range of 75 knots is a differential of 45 knots. This is enough = to climb a few hundred feet much less arrest the rate of descent. Work out = the physics and you can see how much altitude you gain for converting this = much horizontal speed to vertical speed. In sailplanes we expect about an&n= bsp; 800 foot altitude gain in a pull up from 135 knots to 60 knots. Possib= ly a  surprise to people here is that a Lancair will not be much diffe= rent. It is energy conversion not drag that matters.

=
=0A=0A=0A=0A

=0A=0A =

=0A=0A = --0-137306449-1265006273=:77530--