X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 08 May 2012 07:51:23 -0400 Message-ID: X-Original-Return-Path: Received: from elasmtp-dupuy.atl.sa.earthlink.net ([209.86.89.62] verified) by logan.com (CommuniGate Pro SMTP 5.4.5) with ESMTP id 5526856 for lml@lancaironline.net; Mon, 07 May 2012 22:20:05 -0400 Received-SPF: none receiver=logan.com; client-ip=209.86.89.62; envelope-from=colyncase@earthlink.net DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=EHG+uHZu/0yttpvs1PPyvCrK7PKSHmweEch625ChSGbGRkXdBpO2eiFEi8xZk9Fu; h=Received:From:Mime-Version:Content-Type:Subject:Date:In-Reply-To:To:References:Message-Id:X-Mailer:X-ELNK-Trace:X-Originating-IP; Received: from [70.16.68.225] (helo=[192.168.1.24]) by elasmtp-dupuy.atl.sa.earthlink.net with esmtpa (Exim 4.67) (envelope-from ) id 1SRa1N-0006PM-Sk for lml@lancaironline.net; Mon, 07 May 2012 22:19:26 -0400 From: Colyn Case Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: multipart/alternative; boundary=Apple-Mail-121--493403838 Subject: Re: [LML] Re: Necessity of A/C in IV-P? X-Original-Date: Mon, 7 May 2012 22:19:25 -0400 In-Reply-To: X-Original-To: "Lancair Mailing List" References: X-Original-Message-Id: X-Mailer: Apple Mail (2.1084) X-ELNK-Trace: 63d5d3452847f8b1d6dd28457998182d7e972de0d01da9405479b7e4d69750b029f0c01a836ad277350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 70.16.68.225 --Apple-Mail-121--493403838 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 Hi Bob, That would appear to be a huge improvement in that the area of = penetration through the fuselage is greatly reduced. =20 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 wouldn't be comfortable pronouncing = it "safe" especially to others, unless I had had the engineering = analysis done on the resulting entire fuselage structure. =20 Colyn On May 7, 2012, at 7:51 AM, Bob Rickard wrote: Charlie K / Colyn =20 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. I saw an = 8 knot gain in TAS at FL180. My original system was installed in 2001 = time frame (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 and 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 planning a LOBO paper on it sometime = soon. It works very well, looks fantastic, is light (except for the = fan), and is strong and safe. =20 Bob R =20 =20 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? =20 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 "dump" 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. 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. =20 =20 =20 Charlie K. =20 See me on the web at www.Lancair-IV.com =20 =20 From: Colyn Case To: lml@lancaironline.net=20 Sent: Friday, May 4, 2012 8:08 AM Subject: [LML] Re: Necessity of A/C in IV-P? =20 Charlie, how did that work out? You eventually added the airflow = systems unit right? Does that require a hole through the fuselage floor? =20 On May 3, 2012, at 1:20 PM, Charlie Kohler wrote: =20 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. =20 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. =20 Complicated maybe--but it kept the hot turbocharged air out of the = cabin until it was necessary. =20 Charlie K. =20 See me on the web at www.Lancair-IV.com =20 =20 From: Jim Nordin To: lml@lancaironline.net=20 Sent: Thursday, May 3, 2012 8:28 AM Subject: [LML] Necessity of A/C in IV-P? =20 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. 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? =20 LML Gang, =20 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 = aircraft? =20 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 = ambient) and it doesn=92t have the bubble canopy. =20 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? =20 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 =20 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. =20 I appreciate your input. =20 Dan Olsen Fort Collins, CO N320DK =96 640hrs IV-P =96 10% done =20 =20 =20 -- For archives and unsub = http://mail.lancaironline.net:81/lists/lml/List.html --Apple-Mail-121--493403838 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=windows-1252 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 on the main lml page) I personally wouldn't be = comfortable pronouncing it "safe" especially to others, unless I had had = the engineering analysis done 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 scoop = 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 frame (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 and = 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 planning 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
Subj= ect: [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.
 Colyn Case < 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:
 
 Jim Nordin < lml@lancaironline.net 
Sent: Thursday, May 3, 2012 8:28 = AM
Subject: [LML] Necessity of A/C in = IV-P? 
Wouldn=92t it be good to use that air to air heat = exchanger in line with the bleed air to the cabin?
 Lancair Mailing List = [mailto:lml@lancaironline.net] On Behalf Of Dan & Kari = Olsen
Sent: Wednesday, May 02, 2012 = 11:05 AM
To:  [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 aircraft? 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 ambient) 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: Weight