The Murphy Builders Site

Received: from ne.com.au (tc1-60.ne.com.au [203.13.72.252]) by
redback.ne.com.au (8.8.7/8.7.3) with ESMTP id VAA30604 for
<murphy-rebel@dcsol.com>; Sun, 5 Sep 1999 21:57:43 +1000
Message-ID: <37D25B30.A8CF8313@ne.com.au>
Date: Sun, 05 Sep 1999 21:59:44 +1000
From: Ian Donaldson <allsure@ne.com.au>
X-Mailer: Mozilla 4.05 [en] (Win95; I)
MIME-Version: 1.0
To: "(Murphy Rebel Builders List)" <murphy-rebel@dcsol.com>
Subject: Rotax 912S
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

G'day from Australia.

Whilst I am awaiting delivery of my Rebel kit, and having nothing better
to do, I am doing some forward planning.

I have a few questions;

1. Has anyone any experience with this engine in a Rebel?
2. The factory offer a GSC propellor as standard. Are these
satisfactory?
3. The 68" 3 blade has been recommended for the 912S. Any comments?

Regards and thanks

Ian Donaldson






-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

Hi Ian !
I'm surprised you're only getting 80 Kt - have you checked
your ASI against a GPS ?

I used to get 97 mph cruise with the 80 hp. 912, burning
a max. of about 3 imp. gallons/hr. .... 2 1/4 in winter.

Do you have at least 1 notch of negative flapperon for
cruise ?? That will definitely help ! You could try 2 notches,
generally you need about 115 -120 hp to benefit from 2, but it's
worth a try - should give about 3 kt more cruise per notch.

What prop do you have ?? I had a GSC wood ground adjustable.
When re-setting it once, I ended up a bit coarse, and got a
cruise of 110 mph at 5,400 rpm (normal cruise setting) - but the
climb suffered too much, so I 'fined' it down a bit ! ;-)

Glad to hear you've enjoyed your Rebel for over 100 Hr !
We had over 1,000 on ours when we sold it ... Enjoyed every minute !! :-)

.....bobp

-----------------------------------orig.------------------------
At 11:54 PM 6/15/03 +1000, you wrote:

G'day


My Rebel is fitted with the 100hp Rotax and I have over 100 hours on it so
far.

I would like to contact any other Rebel owners who are using the same engine
so that I can compare cruise speeds, fuel burn (etc).

My Rebel generally cruises at 80 knots and uses about 18 litres and hour.


Thanks and regards



Ian Donaldson



*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*

*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

Hi Ian,

What is the empty weight of your Rebel? I'm building light and hoping to use
a light engine some day.

Paul Kucera

Rebel 453R


----- Original Message -----
From: "Ian Donaldson" <allsure@iprimus.com.au>
To: <murphy-rebel@dcsol.com>
Sent: Sunday, June 15, 2003 9:54 AM
Subject: Rotax 912s

G'day


My Rebel is fitted with the 100hp Rotax and I have over 100 hours on it so
far.

I would like to contact any other Rebel owners who are using the same

engine

so that I can compare cruise speeds, fuel burn (etc).

My Rebel generally cruises at 80 knots and uses about 18 litres and hour.


Thanks and regards



Ian Donaldson

*-------------------------------------------------------------------------*

To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com

*-------------------------------------------------------------------------*



*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

Hi Ian !

Fairings will definitely help - we gained 10 mph by fairing
the gear legs, and inner legs & bungees. I'm sure the struts will
help too - ours already had those nice fiberglass fairings (cleaner
than the metal wraps now used). Strips of alum. to fill the gap
in the flapperons will help too.

I know that Rotax recommends a larger oil cooler for the
912-S - hoped it might fit in the same place in the Murphy 912
cowl. Where is yours now ?

Sounds like your prop is so coarse the engine can't develop
full power - these guys like to TURN ! I ran 5,800 + on climb -
gave me 1,100 - 1,200 feet/min. Even a hundred rpm greatly reduced
the power output. You might be very surprised if you let that S
loose - and it might run cooler, too, since it won't be lugging !

My performance matched up pretty well with another 912 Rebel
nearby. He built a very nice looking Rebel that came in about 720 lb.,
painted, with upholstry & instruments. It flew very well with the
regular 912 (80 hp.), and had about the same performance as mine.
What a great airplane, even on 80 hp. !!! :-) :-)

.....bobp

-------------------------------orig.----------------------------------
At 11:44 PM 6/16/03 +1000, you wrote:

: Re: Rotax 912s

G'day Bob
!
I'm surprised you're only getting 80 Kt - have you checked
your ASI against a GPS ?

I have tried a few times, but gave up in the finish! always seems to be too
bumpy or windy to get an acurate reading!

I used to get 97 mph cruise with the 80 hp. 912, burning
a max. of about 3 imp. gallons/hr. .... 2 1/4 in winter.

Well that is amazing!

Do you have at least 1 notch of negative flapperon for
cruise ?? That will definitely help ! You could try 2 notches,
generally you need about 115 -120 hp to benefit from 2, but it's
worth a try - should give about 3 kt more cruise per notch.

I do usr negative flap, and it does help. However I do not have any fairings
on the wing struts or on the bungees. maybe I will put some on when I cane
get some time to play with it. Perhaps that will make a difference.

What prop do you have ?? I had a GSC wood ground adjustable.
When re-setting it once, I ended up a bit coarse, and got a
cruise of 110 mph at 5,400 rpm (normal cruise setting) - but the
climb suffered too much, so I 'fined' it down a bit ! ;-)

I have a three blade Warp Drive that is ground adjustable. I just set it at
the start, and have never touched it since. The engine will turn a maximum
of 5200 on take off, so taking account of what you said about 5400 cruise,
maybe I should fine the pitch back a little. Perhaps that will help. What do
you think?

Glad to hear you've enjoyed your Rebel for over 100 Hr !
We had over 1,000 on ours when we sold it ... Enjoyed every minute !!

:-)
I sure have. There have been some teething problems, mostly eith oil temps.
I have moved the oil cooler three times, and now seem to have the optimal
position. On a cool day (12c) it runs about 80 degrees now. I am still
concerned just what the temp will be when we get back to 40c in Summer. Any
ideas?

Regards


Ian



*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*

*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

G'day


My Rebel is fitted with the 100hp Rotax and I have over 100 hours on it so
far.

I would like to contact any other Rebel owners who are using the same engine
so that I can compare cruise speeds, fuel burn (etc).

My Rebel generally cruises at 80 knots and uses about 18 litres and hour.


Thanks and regards



Ian Donaldson



*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

Hi Ian !

Just one last thought ... try making those fairings
out of Lexan - 3/32" or 1/16". I just re-made mine that way.
Lexan is SO much easier to work - you can bend it several times
without cracks, and trim it with snips. It paints easily too !

The beauty of using Lexan for the gear fairings is -
you can see through it !! No blind back-drilling !!! And ...
if you put a piece of tape over the bolts, etc. before painting,
when you peel it off, you've got a window for inspections !

For the bungee legs, just do one long fairing to cover
the whole leg & bungees. It helps to wrap some thin foam or
rubber around the bungees first, to ease rubbing on the fairing.
The fairing is just a wrap around the leg, going behind the tube
about 3 or 4 inches. This means the trailing edge tapers from the
center to the wheel end - easy if you do it in Bristol Board
first for a pattern.

On the prop - it usually takes about 3 tries to get
the right pitch, but I think you'll be delighted if you can
get her cruising at 5,400 and climbing at 5,800 !

.....bobp

----------------------------------orig.-------------------------
At 10:46 PM 6/17/03 +1000, you wrote:

: Re: Rotax 912s


G'day Bob

Fairings will definitely help - we gained 10 mph by fairing
the gear legs, and inner legs & bungees. I'm sure the struts will
help too - ours already had those nice fiberglass fairings (cleaner
than the metal wraps now used). Strips of alum. to fill the gap
in the flapperons will help too.

Well that's good news. I lost patience with trying to fit those sheet
aluminium ones. just too hard to make look nice. But I had better get back
to making them fit! I have sealed the gap in the flapperons with duct tape
which looks OK and seems to do the job..

I know that Rotax recommends a larger oil cooler for the
912-S - hoped it might fit in the same place in the Murphy 912
cowl. Where is yours now ?

I have just fitted the oil cooler that was supplied in the kit. I have
looked at oil coolers on other 912s engines and my cooler is larger than
those by a reasonable amount. The cooler was first fitted in the space just
under the prop flange and I suspect that it was blanketed by the flange. I
then moved it into the same opening that is used for the water radiator, but
it was not successful, and now it is situated just below where it was first
fitted and it seem to get a look at fresh air there. Summer will tell!

Sounds like your prop is so coarse the engine can't develop
full power - these guys like to TURN ! I ran 5,800 + on climb -
gave me 1,100 - 1,200 feet/min. Even a hundred rpm greatly reduced
the power output. You might be very surprised if you let that S
loose - and it might run cooler, too, since it won't be lugging !

Well that's something to consider. I may just be trying to turn too high a
gear! When I get a chance I will repitch the prop and see what happens. But
I suppose that I could get the other extreme with all revs and no cruise
speed!

My performance matched up pretty well with another 912 Rebel
nearby. He built a very nice looking Rebel that came in about 720 lb.,
painted, with upholstry & instruments. It flew very well with the
regular 912 (80 hp.), and had about the same performance as mine.
What a great airplane, even on 80 hp. !!! :-) :-)

You have given me more heart to get back and experiment. I guess that's why
they are called "experimental" planes!

Thanks again for your input.

Regards

Ian Donaldson





*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*

*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

G'day Ian & Bob !

Rick here in Sydney.... Ian , don't forget , Bob is talking in MILES
per hour and you are talking in KNOTS

80 Knots = about 89 miles per hour !

Hope to see all your "Rebellers" at Oshkosh !!! :-)

Yaaahhhoooooooooooooo !!! :-)
----- Original Message -----
From: Bob Patterson
To: murphy-rebel@dcsol.com
Sent: Monday, June 16, 2003 12:17 AM
Subject: Re: Rotax 912s



Hi Ian !
I'm surprised you're only getting 80 Kt - have you checked
your ASI against a GPS ?

I used to get 97 mph cruise with the 80 hp. 912, burning
a max. of about 3 imp. gallons/hr. .... 2 1/4 in winter.

Do you have at least 1 notch of negative flapperon for
cruise ?? That will definitely help ! You could try 2 notches,
generally you need about 115 -120 hp to benefit from 2, but it's
worth a try - should give about 3 kt more cruise per notch.

What prop do you have ?? I had a GSC wood ground adjustable.
When re-setting it once, I ended up a bit coarse, and got a
cruise of 110 mph at 5,400 rpm (normal cruise setting) - but the
climb suffered too much, so I 'fined' it down a bit ! ;-)

Glad to hear you've enjoyed your Rebel for over 100 Hr !
We had over 1,000 on ours when we sold it ... Enjoyed every minute !!
:-)

.....bobp

-----------------------------------orig.------------------------
At 11:54 PM 6/15/03 +1000, you wrote:

G'day


My Rebel is fitted with the 100hp Rotax and I have over 100 hours on

it so

far.

I would like to contact any other Rebel owners who are using the same

engine

so that I can compare cruise speeds, fuel burn (etc).

My Rebel generally cruises at 80 knots and uses about 18 litres and

hour.

Thanks and regards



Ian Donaldson

*-----------------------------------------------------------------------

--*

To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at

http://rebel:builder@www.dcsol.com:81/default.htm

To contact the list admin, e-mail mike.davis@dcsol.com

*-----------------------------------------------------------------------

--*




*------------------------------------------------------------------------
-*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com

*------------------------------------------------------------------------
-*






*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

:
G'day Paul

Subject: Re: Rotax 912s

What is the empty weight of your Rebel? I'm building light and hoping to

use

a light engine some day.

I have made a very utilitarian Rebel, without any goodies at all, and it
weighs 330kilograms.
It flies just great!

Regards


Ian

Rebel 453R

*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

: Re: Rotax 912s

G'day Bob
!
I'm surprised you're only getting 80 Kt - have you checked
your ASI against a GPS ?

I have tried a few times, but gave up in the finish! always seems to be too
bumpy or windy to get an acurate reading!

I used to get 97 mph cruise with the 80 hp. 912, burning
a max. of about 3 imp. gallons/hr. .... 2 1/4 in winter.

Well that is amazing!

Do you have at least 1 notch of negative flapperon for
cruise ?? That will definitely help ! You could try 2 notches,
generally you need about 115 -120 hp to benefit from 2, but it's
worth a try - should give about 3 kt more cruise per notch.

I do usr negative flap, and it does help. However I do not have any fairings
on the wing struts or on the bungees. maybe I will put some on when I cane
get some time to play with it. Perhaps that will make a difference.

What prop do you have ?? I had a GSC wood ground adjustable.
When re-setting it once, I ended up a bit coarse, and got a
cruise of 110 mph at 5,400 rpm (normal cruise setting) - but the
climb suffered too much, so I 'fined' it down a bit ! ;-)

I have a three blade Warp Drive that is ground adjustable. I just set it at
the start, and have never touched it since. The engine will turn a maximum
of 5200 on take off, so taking account of what you said about 5400 cruise,
maybe I should fine the pitch back a little. Perhaps that will help. What do
you think?

Glad to hear you've enjoyed your Rebel for over 100 Hr !
We had over 1,000 on ours when we sold it ... Enjoyed every minute !!

:-)
I sure have. There have been some teething problems, mostly eith oil temps.
I have moved the oil cooler three times, and now seem to have the optimal
position. On a cool day (12c) it runs about 80 degrees now. I am still
concerned just what the temp will be when we get back to 40c in Summer. Any
ideas?

Regards


Ian



*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

: Re: Rotax 912s


G'day Bob

Fairings will definitely help - we gained 10 mph by fairing
the gear legs, and inner legs & bungees. I'm sure the struts will
help too - ours already had those nice fiberglass fairings (cleaner
than the metal wraps now used). Strips of alum. to fill the gap
in the flapperons will help too.

Well that's good news. I lost patience with trying to fit those sheet
aluminium ones. just too hard to make look nice. But I had better get back
to making them fit! I have sealed the gap in the flapperons with duct tape
which looks OK and seems to do the job..

I know that Rotax recommends a larger oil cooler for the
912-S - hoped it might fit in the same place in the Murphy 912
cowl. Where is yours now ?

I have just fitted the oil cooler that was supplied in the kit. I have
looked at oil coolers on other 912s engines and my cooler is larger than
those by a reasonable amount. The cooler was first fitted in the space just
under the prop flange and I suspect that it was blanketed by the flange. I
then moved it into the same opening that is used for the water radiator, but
it was not successful, and now it is situated just below where it was first
fitted and it seem to get a look at fresh air there. Summer will tell!

Sounds like your prop is so coarse the engine can't develop
full power - these guys like to TURN ! I ran 5,800 + on climb -
gave me 1,100 - 1,200 feet/min. Even a hundred rpm greatly reduced
the power output. You might be very surprised if you let that S
loose - and it might run cooler, too, since it won't be lugging !

Well that's something to consider. I may just be trying to turn too high a
gear! When I get a chance I will repitch the prop and see what happens. But
I suppose that I could get the other extreme with all revs and no cruise
speed!

My performance matched up pretty well with another 912 Rebel
nearby. He built a very nice looking Rebel that came in about 720 lb.,
painted, with upholstry & instruments. It flew very well with the
regular 912 (80 hp.), and had about the same performance as mine.
What a great airplane, even on 80 hp. !!! :-) :-)

You have given me more heart to get back and experiment. I guess that's why
they are called "experimental" planes!

Thanks again for your input.

Regards

Ian Donaldson





*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------

G'day Bob


Thanks for your input and suggestions. the Lexan sounds like an easier way
to make the fairings. It is really hard work trying to bend that springy
aluminium into shape and then making it stay there!

I really did not try all that hard to make the fairings as I just wanted to
get flying, but now I will go back to those details as soon as the daylight
gets a bit longer.

I have not thought much about how to fair the bungies, but your idea sounds
OK to me.

The prop setting has worried me for some time, and I guess that I have not
changed it is just another job that takes time to fix. I will let you know
what difference the changes make.


Regards

Ian



*-------------------------------------------------------------------------*
To unsubscribe from this list go to:
http://www.dcsol.com:81/public/code/html-subscribe.wcx
Archives located at http://rebel:builder@www.dcsol.com:81/default.htm
To contact the list admin, e-mail mike.davis@dcsol.com
*-------------------------------------------------------------------------*








-----------------------------------------------------------------
List archives located at: https://mail.dcsol.com/login
username "rebel" password "builder"
Unsubscribe: rebel-builders-unsubscribe@dcsol.com
List administrator: mike.davis@dcsol.com
-----------------------------------------------------------------