X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 09 May 2012 13:38:38 -0400 Message-ID: X-Original-Return-Path: Received: from mail-yw0-f52.google.com ([209.85.213.52] verified) by logan.com (CommuniGate Pro SMTP 5.4.5) with ESMTPS id 5528056 for lml@lancaironline.net; Tue, 08 May 2012 13:46:22 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.213.52; envelope-from=joeczabaranek@gmail.com Received: by yhpp61 with SMTP id p61so1452263yhp.25 for ; Tue, 08 May 2012 10:45:45 -0700 (PDT) MIME-Version: 1.0 Received: by 10.236.125.234 with SMTP id z70mr1232268yhh.18.1336499145324; Tue, 08 May 2012 10:45:45 -0700 (PDT) Received: by 10.146.77.5 with HTTP; Tue, 8 May 2012 10:45:45 -0700 (PDT) In-Reply-To: References: X-Original-Date: Tue, 8 May 2012 13:45:45 -0400 X-Original-Message-ID: Subject: Re: [LML] Re: Necessity of A/C in IV-P? From: Joseph Czabaranek X-Original-To: Lancair Mailing List Content-Type: multipart/alternative; boundary=485b397dd071ccba0d04bf89f41e --485b397dd071ccba0d04bf89f41e Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Who wants to volunteer to be that test pilot? How would you determine if the nominal Vne has been reduced from flight testing without exceeding it? And then if you do exceed the new Vne I imagine the odds are greater that failure will be catastrophic and sudden rather than gradual. Flight test is a poor choice to determine new structural limits. Validate its within a margin of safety yes... I wouldn't turn off the SAS on an F-16 or change its structural modes in flight to see if the ailerons are coming off without first modeling it on the ground. And that's with an ejection seat. No amount of experience at the controls should make flight testing an attractive option for structural testing after you've cut new holes in the plane. Joe Czabaranek N424DH On Tue, May 8, 2012 at 12:30 PM, Ted Noel wrote: > I've been watching this thread with considerable interest. And all the > concerns seem valid. There seem to be three ways to deal with the problem= : > 1. No A/C. Not a great answer. > 2. Detailed structural analysis. Problematic due to cost, and variability > in individual builds. > 3. Flight testing with a competent test pilot. > > I think #3 is best since it deals with the variabilities of the > installation and creates a hard VNE number. Also, there are a lot of A/C > installations flying. This implies a degree of safety. > > Ted Noel > N540TF > > On 5/8/2012 7:51 AM, Colyn Case wrote: > > Hi Bob, > > That would appear to be a huge improvement in that the area of > penetration through the fuselage is greatly reduced. > Congrats on getting your 8 knots back b.t.w. > However, given all previous discussion (e.g. read the "flutter" article o= n > the main lml page) I personally wouldn't be comfortable pronouncing it > "safe" especially to others, unless I had had the engineering analysis do= ne > on the resulting entire fuselage structure. > > Colyn > > On May 7, 2012, at 7:51 AM, Bob Rickard wrote: > > Charlie K / Colyn**** > ** ** > I just did the opposite this winter, and removed the Airflow systems scoo= p > from my IV-P and engineered a low drag plenum out back. I saw an 8 knot > gain in TAS at FL180. My original system was installed in 2001 time fram= e > (1st flight in =9202), so I don=92t know if it was the =93reduced drag=94 > version. I=92m very aware of the topic of cutting holes in the fuselage= and > took great care to overdesign the modification and have a carbon expert > build and install it. There are bids of reinforcing carbon both inside a= nd > outside the fuselage that are cut well beyond the scoops, which are also > made of carbon and hysol=92d in. A couple of pics attached, I=92m plann= ing a > LOBO paper on it sometime soon. It works very well, looks fantastic, is > light (except for the fan), and is strong and safe.**** > ** ** > Bob R**** > ** ** > ** ** > *From:* Lancair Mailing List [mailto:lml@lancaironline.net > ] *On Behalf Of *Charlie Kohler > *Sent:* Friday, May 04, 2012 9:26 AM > *To:* lml@lancaironline.net > *Subject:* [LML] Re: Necessity of A/C in IV-P?**** > ** ** > hi Colyn**** > Yes-it worked out fine. By that- I mean- it was the best you can do.**** > In the beginning, The pressurized IVs had the cabin intercooler located > on the side of the left lower cowling- with louvers. The intake air was > taken from the engine air cleaner box. Even after moving the intercooler = to > the front/left side the air (thanks Don) into the cabin was measured at > 105=B0on the 70=B0 day.**** > What I didn't say in the post yesterday was that selecting 11,000 feet > on the controller put an electrical signal to the outflow valve to open i= t > wide open. You also could use the "dump" switch to open the valve. That > helps a lot. But the big Issue is to shut off that 105=B0 air from enteri= ng > the cabin.**** > I liked the idea of the Airflow design--but I heard stories of airspeed > penalties with the P51 scoop. I asked Bill Genevro if he had ever > considered doing wind tunnel testing.Then they did-- at Ohio University. > They tucked the condenser up closer to the fuselage and drag reduced > drastically. I bought his system. At that time there was no choice. I di= d > testing later and saw less than three knot change--. The only holes cut i= n > the fuselage was a pair of 1 inch holes for freon in and out of the > condenser. The beautiful part of it, is that --it works. Very well! In al= l > regimes.**** > ** ** > ** ** > ** ** > Charlie K.**** > **** > See me on the web at**** > www.Lancair-IV.com**** > **** > ** ** > ------------------------------ > *From:* Colyn Case > *To:* lml@lancaironline.net > *Sent:* Friday, May 4, 2012 8:08 AM > *Subject:* [LML] Re: Necessity of A/C in IV-P?**** > ** ** > Charlie, how did that work out? You eventually added the airflow > systems unit right?**** > Does that require a hole through the fuselage floor?**** > ** ** > On May 3, 2012, at 1:20 PM, Charlie Kohler wrote:**** > ** ** > LML gang**** > In the years before AC was available, I developed a plan for Summer > (hot) flying. On take off I set the controller to 11,000 feet with the > Pressurized air to the cabin OFF. I opened the air valve from the fresh a= ir > from the vertical stabilizer.**** > ** ** > I took off and climbed to 11,000 feet . At 10,000 feet I closed the > fresh aHim himir from the vertical stabilizer and gradually selected the > pressurized air to the cabin to the ON position. Then as I continued to > climb I selected the cruise altitude on the pressurization controller and > adjusted the rate knob to 200 feet a minute descent. The cabin would then > descend and level off 1000 feet above selected altitude.**** > On the descent into the landing airport-- I set the controller to 1000 > feet above field elevation.**** > ** ** > Complicated maybe--but it kept the hot turbocharged air out of the > cabin until it was necessary.**** > **** > Charlie K.**** > **** > See me on the web at**** > www.Lancair-IV.com**** > **** > ** ** > ------------------------------ > *From:* Jim Nordin > *To:* lml@lancaironline.net > *Sent:* Thursday, May 3, 2012 8:28 AM > *Subject:* [LML] Necessity of A/C in IV-P?**** > ** ** > It can be really warn even at 17,000 feet without A/C in an IV-PT. Why? > The bleed air is super warm. Absolutely necessary? Not IMHO. But a few > letdowns from 20k+ and a drip drip drip off the end of your nose will tel= l > you it=92s nice. Or in summer heat in Houston, Phoenix or some other saun= a, > it is even better than nice.**** > Wouldn=92t it be good to use that air to air heat exchanger in line with > the bleed air to the cabin?HEAVY.**** > Jim**** > ------------------------------ > *From:* Lancair Mailing List [mailto:lml@lancaironline.net > ] *On Behalf Of *Dan & Kari Olsen > *Sent:* Wednesday, May 02, 2012 11:05 AM > *To:* lml@lancaironline.net > *Subject:* [LML] Necessity of A/C in IV-P?**** > **** > LML Gang,**** > **** > With all the discussion of structural integrity compromises of the IV-P > fuselage by cutting air conditioning holes, I have a question for you > seasoned IV-P drivers=85 How necessary is air conditioning in this aircr= aft? > **** > **** > I have been flying my 320 for almost 9 years now and certainly would > love to have had it during ground operations on hot summer days with the > green house canopy. However, once moving and at altitude, there is no > need. I realize that the IV-P is going to have warmer air because of the > pressurization but it is also typically flying much higher (colder ambien= t) > and it doesn=92t have the bubble canopy.**** > **** > So, in normal cross country cruise operations above FL180, do any of you > that don=92t have A/C **really** wish that you had it?**** > **** > I=92m early in the building of my IV-P and don=92t want to put it in for > several reasons:**** > =B7 Weight**** > =B7 Potential structural issues**** > =B7 Cost**** > =B7 One more thing to break down the road**** > **** > I live in Colorado and will be using this plane as a cross country > traveler with my wife, so comfort is certainly a factor but not at all > costs. One thought is to get one of those cooler-with-ice-and-a-fan > systems to toss in the back seat for those few days that are very hot.***= * > **** > I appreciate your input.**** > **** > Dan Olsen**** > Fort Collins, CO**** > N320DK =96 640hrs**** > IV-P =96 10% done**** > > ** ** > ** ** > > ** ** > -- > For archives and unsub > http://mail.lancaironline.net:81/lists/lml/List.html > > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2012.0.2171 / Virus Database: 2425/4985 - Release Date: 05/08/12 > > --485b397dd071ccba0d04bf89f41e Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Who wants to volunteer to be that test pilot? =A0How would you determine if= the nominal Vne has been reduced from flight testing without exceeding it?= =A0And then if you do exceed the new Vne I imagine the odds are greater th= at failure will be catastrophic and sudden rather than gradual. =A0Flight t= est is a poor choice to determine new structural limits. =A0Validate its wi= thin a margin of safety yes...

I wouldn't turn off the SAS on an F-16 or change its str= uctural modes in flight to see if the ailerons are coming off without first= modeling it on the ground. =A0And that's with an ejection seat. =A0No = amount of experience at the controls should make flight testing an attracti= ve option for structural testing after you've cut new holes in the plan= e.

Joe Czabaranek
N424DH

On Tue, May 8, 2012 at 12:30 PM, Ted Noel <= tednoel@cfl.rr.com<= /a>> wrote:
=20 =20 =20
I've been watching this thread with considerable interest. And all the concerns seem valid. There seem to be three ways to deal with the problem:
1. No A/C.=A0 Not a great answer.
2. Detailed structural analysis. Problematic due to cost, and variability in individual builds.
3. Flight testing with a competent test pilot.

I think #3 is best since it deals with the variabilities of the installation and creates a hard VNE number. Also, there are a lot of A/C installations flying. This implies a degree of safety.

Ted Noel
N540TF

On 5/8/2012 7:51 AM, Colyn Case wrote:
Hi Bob,

That would appear to be a huge improvement in that the area of penetration through the fuselage is greatly reduced. =A0
Congrats on getting your 8 knots back b.t.w.
However, given all previous discussion (e.g. read the "flutter" article on the main lml page) I personally woul= dn't be comfortable pronouncing it "safe" especially to others, u= nless I had had the engineering analysis done on the resulting entire fuselage structure. =A0

Colyn

On May 7, 2012, at 7:51 AM, Bob Rickard wrote:

Charlie K / Colyn
=A0
I just did the opposite this winter, and removed the Airflow systems scoop from my IV-P and engineered a low drag plenum out back.=A0 I saw an 8 knot gain in TAS at FL180.=A0 My original system was installed in 2001 time frame (1st=A0flight in =9202), so I don=92t know if it was the =93reduced drag= =94 version.=A0 =A0I=92m very aware of the topic of cutting holes in the fuselage and took great care to overdesign the modification and have a carbon expert build and install it. =A0There are bids of reinforcing carbon both inside and outside the fuselage that are cut well beyond the scoops, which are also made of carbon and hysol=92d in.=A0 =A0A couple of pics attache= d, I=92m planning a LOBO paper on it sometime soon.=A0 It works very well, looks fantastic, is light (except for the fan), and is strong and safe.
=A0
Bob R
=A0
=A0
=A0
hi Colyn
Yes-it worked out fine. By that- I mean- it was the best you can do.
In the beginning, The pressurized IVs had the cabin intercooler located on the side of the left lower cowling- with louvers. The intake air was taken from the engine air cleaner box. Even after moving the intercooler to the front/left side the air (thanks Don) into the cabin was measured at 105=B0on the 70=B0 day.
What I didn't say in the post yesterday was that selecting 11,000 feet on the controller put an electrical signal to the outflow valve to open it wide open. You also could use the "dum= p" switch to open the valve. That helps a lot. But the big Issue is to shut off that 105=B0 air from entering the cabin.
I liked the idea of the Airflow design--but I heard stories of airspeed penalties with the P51 scoop. I asked Bill Genevro if he had ever considered doing wind tunnel testing.Then they did-- at Ohio University. They tucked the condenser up closer to the fuselage and drag reduced drastically. I bought his system. At that time there was no choice.=A0 I did testing later and saw less than three knot change--. The only holes cut in the fuselage was a pair of 1 inch holes for freon in and out of the condenser. The beautiful part of it, is that --it works. Very well! In all regimes.
=A0
=A0
=A0
Charlie K.
=A0
See me on the web at
=A0
=A0
=
From:=A0Colyn Case <colyn= case@earthlink.net>
To:=A0lml@lancaironline.net=A0
Sent:=A0Friday, May 4, 2012 8:08 AM
Subject:=A0[LML] Re: Necessity of A/C in IV-P?
=A0
Charlie, how did that work out? =A0 You eventually added the airflow systems unit right?
Does that require a hole through the fuselage floor?
=A0
On May 3, 2012, at 1:20 PM, Charlie Kohler wrote:
=A0=
LML gang
In the years before AC was available, I developed a plan for Summer (hot) flying. On take off I set the controller to 11,000 feet with the Pressurized air to the cabin OFF. I opened the air valve from the fresh air from the vertical stabilizer.
=A0
I took off and climbed to 11,000 feet . At 10,000 feet I closed the fresh aHim himir from the vertical stabilizer and gradually selected the pressurized air to the cabin to the ON position. Then as I continued to climb I selected the cruise altitude on the pressurization controller and adjusted the rate knob to 200 feet a minute descent. The cabin would then descend and level off 1000 feet above selected altitude.
On the descent into the landing airport-- I set the controller to 1000 feet above field elevation.
=A0
Complicated maybe--but it=A0 kept the hot turbocharged air out of the cabin until it was necessary.
=A0
Charlie K.
=A0
See me on the web at
=A0
=A0
From:=A0Jim Nordin <panelmaker@earthlink.net>
To:=A0lml@lancaironline.net=A0
Sent:=A0Thu= rsday, May 3, 2012 8:28 AM
Subject:=A0= [LML] Necessity of A/C in IV-P?
=A0
It can be really warn even at 17,000 feet without A/C in an IV-PT. Why? The bleed air is super warm. Absolutely necessary? Not IMHO. But a few letdowns from 20k+ and a drip drip drip off the end of your nose will tell you it=92s nice. Or in summer heat in Houston, Phoenix or some other sauna, it is even better than nice.<= u>
Wouldn=92t it be good to use that air to air heat exchanger in line with the bleed air to the cabin?HEAVY.
Jim=
From:=A0Lancair Mailing= List [mailto:lml@lancaironline.net]=A0On Behalf Of=A0Dan & Kari Olsen
Sent:=A0Wednesday, May 02, 2012 11:05 AM
To:=A0lml@lancaironline.net
Subject:= =A0[LML] Necessity of A/C in IV-P?<= /span>
=A0<= /span>
LML Gang,<= u>
=A0<= /span>
With all the discussion of structural integrity compromises of the IV-P fuselage by cutting air conditioning holes, I have a question for you seasoned IV-P drivers=85=A0 How necessary is air conditioning in this aircraft?
=A0<= /span>
I have been flying my 320 for almost 9 years now and certainly would love to have had it during ground operations on hot summer days with the green house canopy.=A0 However, once moving and at altitude, there is no need.=A0 I realize that the IV-P is going to have warmer air because of the pressurization but it is also typically flying much higher (colder ambient) and it doesn=92t have the bubble canopy.
=A0<= /span>
So, in normal cross country cruise operations above FL180, do any of you that don=92t have A/C *really* wish that you had it?
=A0<= /span>
I=92m early in the building of my IV-P and don=92t want to put it in for several reasons:
=B7=A0=A0=A0= =A0=A0=A0=A0=A0=A0Weight
=B7=A0=A0=A0= =A0=A0=A0=A0=A0=A0Potential structural issues
=B7=A0=A0=A0= =A0=A0=A0=A0=A0=A0Cost=
=B7=A0=A0=A0= =A0=A0=A0=A0=A0=A0One more thing to break down the road
=A0<= /span>
I live in Colorado and will be using this plane as a cross country traveler with my wife, so comfort is certainly a factor but not at all costs.=A0 One thought is to get one of those cooler-with-ice-and-a-fan systems to toss in the back seat for those few days that are very hot.
=A0<= /span>
I appreciate your input.
=A0<= /span>
Dan Olsen<= u>
Fort Collins, CO
N320DK =96 640hrs
IV-P =96 10% done

=A0

=A0

=A0

<IMG_0568.jpeg><IMG_0566.jpeg>= <IMG_0534.jpeg><IMG_0594.jpeg>= --
For archives and unsub=A0http://mail.lancaironline.net:81/lists/lml/= List.html

No virus found in this message.
Checked by AVG - w= ww.avg.com
Version: 2012.0.2171 / Virus Database: 2425/4985 - Release Date: 05/08/12


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