X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fed1rmmtao07.cox.net ([68.230.241.32] verified) by logan.com (CommuniGate Pro SMTP 5.0c1) with ESMTP id 678895 for flyrotary@lancaironline.net; Tue, 23 Aug 2005 10:11:20 -0400 Received-SPF: none receiver=logan.com; client-ip=68.230.241.32; envelope-from=ALVentures@cox.net Received: from BigAl ([68.7.14.39]) by fed1rmmtao07.cox.net (InterMail vM.6.01.04.00 201-2131-118-20041027) with ESMTP id <20050823141035.GCQG25443.fed1rmmtao07.cox.net@BigAl> for ; Tue, 23 Aug 2005 10:10:35 -0400 From: "Al Gietzen" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Fire extinguishers Date: Tue, 23 Aug 2005 07:10:46 -0700 Message-ID: <000001c5a7ec$74e67d30$6400a8c0@BigAl> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0001_01C5A7B1.C889EF20" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 This is a multi-part message in MIME format. ------=_NextPart_000_0001_01C5A7B1.C889EF20 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable =20 >the only way to keep the fire out is to keep the air out >being able to shut the cooling air flow, at the exit or intake will = help a lot. =20 I'm trying to put this in perspective. Assuming no way to shut off the intake air, is firing a halon = extinguisher in flight going to have ANY worthwhile impact on an engine fire? Keep in mind that the fiberglass cowl is likely to be breached early on, thus = any control of airflow is lost. I'm beginning to think that the most = important issues here are detection, and removal of the source (fuel) and that an extinguisher would be useful to save the plane once landed, but = worthless (and wasted) if used while airborne. =20 Not that I like the conclusion, but I tend to agree with this = assessment. Early detection and shutdown of the fuel sources is key. Containment of = the fire - keep it out of the cabin, protect the flight controls, and = protect the wiring for a restart when you have no other option than a rocky = hillside - is also very important. =20 I have spare thermocouple inputs to the EM-2 in the area of the fuel = rail and exhaust with temp limits set to trigger the engine alarm in the = event of a high reading. It was the simplest approach. Better would be to wire = in a heat fused link to a separate alarm so you wouldn't have to first figure = out which channel is triggering the alarm. =20 I don't know that having the engine in back is advantageous or not, but = one disadvantage in the canard configuration (at least the Velocity) is the having the aileron push-pull cables running inside the cowling. I have = high temp cables that I intend to firesleeve, but they do have some sort of plastic outer sleeve which will likely burn/melt and could result in difficulties with control. =20 I have a SS sheet (I think 26 guage) backed by fiberfrax for firewall protection. =20 Al =20 =20 ------=_NextPart_000_0001_01C5A7B1.C889EF20 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

 

>the only way to keep the fire out is to keep the air out

>being able to shut the cooling air flow, at the exit or intake will help = a

lot.

 

I'm trying to put this in perspective.

Assuming no way to shut off the intake air, is firing a halon = extinguisher

in flight going to have ANY worthwhile impact on an engine fire? Keep = in

mind that the fiberglass cowl is likely to be breached early on, thus = any

control of airflow is lost. I'm beginning to think that the most = important

issues here are detection, and removal of the source (fuel) and that = an

extinguisher would be useful to save the plane once landed, but = worthless

(and wasted) if used while airborne.

 

Not that I = like the conclusion, but I tend to agree with this assessment.  Early = detection and shutdown of the fuel sources is key. Containment of the fire - keep it = out of the cabin, protect the flight controls, and protect the wiring for a = restart when you have no other option than a rocky hillside - is also very = important.

 <= /font>

I have spare thermocouple inputs to the EM-2 in the area of the fuel rail and exhaust = with temp limits set to trigger the engine alarm in the event of a high = reading. It was the simplest approach.  Better would be to wire in a heat fused = link to a separate alarm so you wouldn’t have to first figure out which channel is triggering the alarm.

 <= /font>

I don’t = know that having the engine in back is advantageous or not, but one = disadvantage in the canard configuration (at least the Velocity) is the having the = aileron push-pull cables running inside the cowling.  I have high temp = cables that I intend to firesleeve, but they do have some sort of plastic outer = sleeve which will likely burn/melt and could result in difficulties with = control.

 <= /font>

I have a SS = sheet (I think 26 guage) backed by fiberfrax for firewall = protection.

 <= /font>

Al

 <= /font>

 <= /font>

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