X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Thu, 13 Apr 2006 00:20:59 -0400 Message-ID: X-Original-Return-Path: Received: from web34911.mail.mud.yahoo.com ([209.191.68.190] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with SMTP id 1066996 for lml@lancaironline.net; Wed, 12 Apr 2006 21:22:45 -0400 Received-SPF: none receiver=logan.com; client-ip=209.191.68.190; envelope-from=n103md@yahoo.com Received: (qmail 12445 invoked by uid 60001); 13 Apr 2006 01:22:02 -0000 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=Message-ID:Received:Date:From:Subject:To:MIME-Version:Content-Type:Content-Transfer-Encoding; b=XDnNh/OX5jl01cubfm6mfOPkwv1MLAZbljNLNYbITIn12Y0JxdPb2RgGb95s8WYEK5D3BnVW5A0LG0nbGreAhm0Z5ypJh9AsS1+JlYtYp/alvYD8fDlWL0C8vwHrJOmcgQf39gTmMa9mOLnfoZO2Jj65w0DDCtBOJyhyyOTTOpU= ; X-Original-Message-ID: <20060413012202.12443.qmail@web34911.mail.mud.yahoo.com> Received: from [12.146.139.19] by web34911.mail.mud.yahoo.com via HTTP; Wed, 12 Apr 2006 18:22:02 PDT X-Original-Date: Wed, 12 Apr 2006 18:22:02 -0700 (PDT) From: bob mackey Subject: Re: fixed-pitch prop X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="0-1688331013-1144891322=:10484" Content-Transfer-Encoding: 8bit --0-1688331013-1144891322=:10484 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Grayhawk wrote: > Bob, I am glad to see you mention the 10:1 ratio, would you use > that ratio if you lost the engine and the prop was still rotating? First, I should say that I probably have more engine-out and off-airport landings than landings at airports and with an engine. I've been flying hanggliders and sailplanes for 20+ years. There's a cliche about the glider pilot who goes to get his engine rating added to his pilot license. After a few lessons, the instructor pulls the throttle. While most power pilots tense up at this point, the glider pilot heaves a sigh of relief and continues the flight to the planned destination :-) Occasionally that is literally true. Back to the Lancair though... it would take a tremendous thermal to climb away from the ground without the engine, so assume I'll be landing soon after the engine quits. In still air, with mixture pulled to cutoff, I see about 700 fpm descent at 100 kias. That's pretty close to Paul's 15:1 idle-glide ratio. If the engine quits over inhospitable terrain, I'll figure about 500 ft lost per mile. I'll also be aiming for a field within about 7:1 glide to a point 1000 feet above the field. I'll be using visual cues primarily. With my thumb against the bridge of my nose, I put the top of my index finger on the horizon. If I can see something under the finger, I can fly to it with a 7:1 glide. For 15:1, I use the tip of my thumb against my forehead and put my pinky fingernail on the horizon. The pad of the pinky is little better than 15:1. Likewise I fly angles through the pattern to landing rather than numbers. This is especially important at a field you've never seen before, at an unknown altitude, and with no services (or paved runways). I could go on for hours about how to identify a good field versus a bad field for landing. There are literally hundreds of visual cues you can use to identify a field's slope, texture, hardness and so on. Similarly there are many ways to see wind direction without a windsock or an AWOS. One of these days, I'll go out to Castle Air Force Base and measure the glide ratio of my 235 with the prop stopped. If I can stop the prop, I'll measure sink rate at a few speeds before landing on the 12000 foot runway. Like Gary, I'll be using about 3000 feet of that for the actual landing. -bob mackey --------------------------------- Blab-away for as little as 1¢/min. Make PC-to-Phone Calls using Yahoo! Messenger with Voice. --0-1688331013-1144891322=:10484 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Grayhawk wrote:
> Bob, I am glad to see you mention the 10:1 ratio, would you use
> that ratio if you lost the engine and the prop was still rotating?

First, I should say that I probably have more engine-out and off-airport
landings than landings at airports and with an engine. I've been flying
hanggliders and sailplanes for 20+ years. There's a cliche about the
glider pilot who goes to get his engine rating added to his pilot license.
After a few lessons, the instructor pulls the throttle. While most power
pilots tense up at this point, the glider pilot heaves a sigh of relief
and continues the flight to the planned destination :-)
Occasionally that is literally true.

Back to the Lancair though... it would take a tremendous thermal
to climb away from the ground without the engine, so assume
I'll be landing soon after the engine quits. In still air, with mixture
pulled to cutoff, I see about 700 fpm descent at 100 kias.
That's pretty close to Paul's 15:1 idle-glide ratio.

If the engine quits over inhospitable terrain, I'll figure about
500 ft lost per mile. I'll also be aiming for a field within about
7:1 glide to a point 1000 feet above the field.
I'll be using visual cues primarily.  With my thumb against the
bridge of  my nose, I put the top of my index finger on the horizon.
If I can see something under the finger, I can fly to it with a 7:1 glide.

For 15:1, I use the tip of my thumb against my forehead and
put my pinky fingernail on the horizon. The pad of the pinky is
little better than 15:1.

Likewise I fly angles through the pattern to landing rather than numbers.
This is especially important at a field you've never seen before, at
an unknown altitude, and with no services (or paved runways).
I could go on for hours about how to identify a good field versus a
bad field for landing. There are literally hundreds of visual cues you
can use to identify a field's slope, texture, hardness and so on.
Similarly there are many ways to see wind direction without a
windsock or an AWOS.

One of these days, I'll go out to Castle Air Force Base and measure the
glide ratio of my 235 with the prop stopped. If I can stop the prop, I'll measure
sink rate at a few speeds before landing on the 12000 foot runway.
Like Gary, I'll be using about 3000 feet of that for the actual landing.

-bob mackey

Blab-away for as little as 1¢/min. Make PC-to-Phone Calls using Yahoo! Messenger with Voice. --0-1688331013-1144891322=:10484--