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Bob, Just went back and looked up elevation of airport I deadsticked into
and its
979 ft so say 1000 ft above sea level. Adding that to my calculation of
1137 would have given me 2137 ft AGL at arrival at the airport. That is
why
I had the impression of having to lose quite a bit of altitude - its
because
I had a bit to lose.
So at 750 fpm I could have glide another 2.85 minutes before running out
of
altitude which at 85 mph = 85*2.85/60 = 4 additional miles. But, very
happy to have arrived with that much altitude to lose.
Ed
----- Original Message -----
From: "Ed Anderson" <eanderson@carolina.rr.com>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Monday, December 13, 2004 11:54 AM
Subject: Re: [FlyRotary] Re: Glide distances
> Yes, Bob. This was with the 2.17 gearbox and 68x72" prop. The RV
> reportedly has a glide ratio of 10:1. So with 9500 MSL (actually about
7500
> AGL), I should have been able to glide 10*7500 = 75,000 ft = 14.2 miles.
> So at 14.2-12 Miles =2.2 miles at 87 mph = 2.2/87 = .0252 hr = 1.5
minutes
> at 750 fpm (of course was not constant but mostly 750) = 1137 ft at the
end
> of my 12 mile glide at the airport. So fairly close to my estimate of
> altitude (also the airport may not have been 2000 above sea level.
>
> In anycase, even with a 10:1 glide ratio (or less) you can still have a
fair
> chance of finding a spot to set it down and walk away depending on
altitude
> of course.
>
> Ed Anderson
>
>
> ----- Original Message -----
> From: "Bob White" <bob@bob-white.com>
> To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
> Sent: Monday, December 13, 2004 11:39 AM
> Subject: [FlyRotary] Re: Glide distances
>
>
> > Ed,
> >
> > That's excellent. Your engine quits so you go into test pilot mode
and
> > get all the data you can. Glide is one advantage you RV guys will
have
> > over me I think. From what I've heard, the BD-4 glides a little
better
> > than a rock with power off. I've only got 2 hours flying time in it,
so
> > I'm a little lite on first hand experience. Hopefully soon.
> >
> > Was this before you upgraded to the "monster" prop?
> >
> > Bob White
> >
> > On Mon, 13 Dec 2004 10:47:45 -0500
> > "Ed Anderson" <eanderson@carolina.rr.com> wrote:
> >
> > > On my 12 mile engine out glide, I punched up the NRST button on my
GPS
> > > to find the two closest airfields were both 12 miles away (gulp!).
> > > Since I knew I was going to be gliding around 85 mph that any sort
of
> > > headwind would considerably shorten the glide. Fortunately I had
been
> > > paying attention to the wind direction as I was outrunning a cold
> > > front, so turned 120 degs for the downwind field.
> > >
> > > From 9500 MSL I arrived over the selected airfield with approx
> > > 1500-2000 ft AGL. I had altitude to do a 360 and a couple of hard
> > > "S" turns to loose altitude and even then came over the fence at
100
> > > mph. This with a stubby wing RV-6A.
> > >
> > > I did have time in that 8 minute glide to find out that my best
glide
> > > speed (at that weight) was 87 MPH which produced a 750 fpm rate of
> > > descent. Any slower the rate went up and any faster the rate went
up.
> > > Also were I found what airspeeds the prop would stop at as well as
> > > what it took to get it going again. So a rather productive 8
minutes
> > > all things considered {:>).
> > >
> > > Ed Anderson
> >
> >
> > --
> > http://www.bob-white.com
> > N93BD - Rotary Powered BD-4 (soon)
> >
> > >> Homepage: http://www.flyrotary.com/
> > >> Archive: http://lancaironline.net/lists/flyrotary/List.html
> >
>
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