A aviation & planes forum. AviationBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AviationBanter forum » rec.aviation newsgroups » Soaring
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

Nitrous Oxide for towing safety?



 
 
Thread Tools Display Modes
  #1  
Old March 4th 04, 12:06 AM
Jason Payne
external usenet poster
 
Posts: n/a
Default Nitrous Oxide for towing safety?

Just a thought. Wanted to see what you guys thought. I know that FAA
aproval would never happen, but seems like a good idea to me.

You could easily and safely run a 100hp shot of NO2 for the first 10-15
seconds of a takeoff roll in an 0-470 or similar motor, and get to 100 feet
and 65 knots a lot quicker than without, increasing safety margins.

NO2 is especially nice in a heat soaked motor because the shot cools the
intake air a good 30-50 degrees...

From being in a ASH-25 at a full 750 kilos on a hot Uvalde day that another
100 hp would really help getting off the ground if you are not behind a big
motor like Scratch.


  #2  
Old March 4th 04, 01:06 AM
Jim Phoenix
external usenet poster
 
Posts: n/a
Default

Back in the old days water-meth worked pretty well, same basic effect. I
think Metros still use it, at least they did 10 years ago. Handy in the
Convair 580's as well - like, they needed more horsepower?

You just needed to be careful not to run out of water-meth at the wrong
time.

Jim

"Jason Payne" wrote in message
...
Just a thought. Wanted to see what you guys thought. I know that FAA
aproval would never happen, but seems like a good idea to me.

You could easily and safely run a 100hp shot of NO2 for the first 10-15
seconds of a takeoff roll in an 0-470 or similar motor, and get to 100

feet
and 65 knots a lot quicker than without, increasing safety margins.

NO2 is especially nice in a heat soaked motor because the shot cools the
intake air a good 30-50 degrees...

From being in a ASH-25 at a full 750 kilos on a hot Uvalde day that

another
100 hp would really help getting off the ground if you are not behind a

big
motor like Scratch.




  #3  
Old March 5th 04, 12:43 PM
Dave Nadler YO
external usenet poster
 
Posts: n/a
Default

Did you mean nitrous for the tow-pilot ?
Easier installation and a more pleasurable view of the trees
at the end of the runway ?
See ya, Dave

"Jason Payne" wrote in message ...
Just a thought. Wanted to see what you guys thought. I know that FAA
aproval would never happen, but seems like a good idea to me.

You could easily and safely run a 100hp shot of NO2 for the first 10-15
seconds of a takeoff roll in an 0-470 or similar motor, and get to 100 feet
and 65 knots a lot quicker than without, increasing safety margins.

NO2 is especially nice in a heat soaked motor because the shot cools the
intake air a good 30-50 degrees...

From being in a ASH-25 at a full 750 kilos on a hot Uvalde day that another
100 hp would really help getting off the ground if you are not behind a big
motor like Scratch.

  #4  
Old March 5th 04, 03:25 PM
Joseph L. Hyde
external usenet poster
 
Posts: n/a
Default

"BACK IN THE OLD DAYS" Hey I've flown planes recently using water
meth.....rolls dart and garretts.....oh wait that has been over 20 years
ago....never mind.....






"Jim Phoenix" wrote in message
...
Back in the old days water-meth worked pretty well, same basic effect. I
think Metros still use it, at least they did 10 years ago. Handy in the
Convair 580's as well - like, they needed more horsepower?

You just needed to be careful not to run out of water-meth at the wrong
time.

Jim

"Jason Payne" wrote in message
...
Just a thought. Wanted to see what you guys thought. I know that FAA
aproval would never happen, but seems like a good idea to me.

You could easily and safely run a 100hp shot of NO2 for the first 10-15
seconds of a takeoff roll in an 0-470 or similar motor, and get to 100

feet
and 65 knots a lot quicker than without, increasing safety margins.

NO2 is especially nice in a heat soaked motor because the shot cools the
intake air a good 30-50 degrees...

From being in a ASH-25 at a full 750 kilos on a hot Uvalde day that

another
100 hp would really help getting off the ground if you are not behind a

big
motor like Scratch.






  #5  
Old March 5th 04, 04:31 PM
Jim Phoenix
external usenet poster
 
Posts: n/a
Default

Back in the REAL old days, we had alcohol tanks in the DC-4's, but not for
water meth, for the props. Lessee - those REAL old days were back in 1985 -
the last millennium.

But back to the subject at hand - shooting nitrous into a Lycoming presents
its engineering challenges, I suppose there are other methods of increasing
acceleration at takeoff. At Sugarbush they do a modified angle takeoff roll,
the geometry of that seemes to increase the initial tow speed, very
slightly. (The towplane is on the main runway - the glider in the grass to
the right , aft of the towplane. The glider is angled towards the runway anf
rolls up onto the runway during the takeoff roll.

Jim

"Joseph L. Hyde" wrote in message
.. .
"BACK IN THE OLD DAYS" Hey I've flown planes recently using water
meth.....rolls dart and garretts.....oh wait that has been over 20 years
ago....never mind.....






"Jim Phoenix" wrote in message
...
Back in the old days water-meth worked pretty well, same basic effect. I
think Metros still use it, at least they did 10 years ago. Handy in the
Convair 580's as well - like, they needed more horsepower?

You just needed to be careful not to run out of water-meth at the wrong
time.

Jim

"Jason Payne" wrote in message
...
Just a thought. Wanted to see what you guys thought. I know that FAA
aproval would never happen, but seems like a good idea to me.

You could easily and safely run a 100hp shot of NO2 for the first

10-15
seconds of a takeoff roll in an 0-470 or similar motor, and get to 100

feet
and 65 knots a lot quicker than without, increasing safety margins.

NO2 is especially nice in a heat soaked motor because the shot cools

the
intake air a good 30-50 degrees...

From being in a ASH-25 at a full 750 kilos on a hot Uvalde day that

another
100 hp would really help getting off the ground if you are not behind

a
big
motor like Scratch.








  #6  
Old March 5th 04, 09:43 PM
Bill Daniels
external usenet poster
 
Posts: n/a
Default

OK, I guess this is a top post thread.

It ain't horsepower, it's the PROP. To improve the 0 - 20 acceleration,
improve the propeller. Have you ever tried to figure out how much power
actually gets to the tow hook on the glider from a 260 HP Pawnee? Maybe 20
HP?

At low speeds, as at the beginning of the TO roll, the tug's prop is mostly
stalled and converting little of the engines HP to thrust. As it
accelerates, more of the prop disc becomes unstalled and the prop picks up
efficiency and therefore more acceleration. A headwind helps a lot here.

So, what to do?

1. A constant speed prop reduces the blade AOA and lets the engine rev to
its redline RPM. (Noisy)
2. Big, slow turning props make much more thrust at low speeds than small,
high RPM props. (Quieter but require PRSU gearbox)
3. Ducted fans work really well at low speeds but lose out to a standard
prop at 100 MPH +. (A LOT quieter)

The ducted fan looks very good in that it can turn at crankshaft RPM while
producing several times the thrust of an unshrouded prop at zero airspeed.

So, why don't you folks living in a country blessed with friendly regulators
design and build a certified ducted fan tug using the minimum engine
necessary - say a 140 HP LOM M132CE. (Less fuel, less noise).
See: http://www.moraviation.com/

I imagine an airframe that looks somewhat like an Ogar. A cute trick would
be to make the fan and duct as one rotating unit constructed of carbon
fiber - this eliminates the problem of fan tip-duct clearance.

Bill Daniels


"Jim Phoenix" wrote in message
...
Back in the REAL old days, we had alcohol tanks in the DC-4's, but not for
water meth, for the props. Lessee - those REAL old days were back in

1985 -
the last millennium.

But back to the subject at hand - shooting nitrous into a Lycoming

presents
its engineering challenges, I suppose there are other methods of

increasing
acceleration at takeoff. At Sugarbush they do a modified angle takeoff

roll,
the geometry of that seemes to increase the initial tow speed, very
slightly. (The towplane is on the main runway - the glider in the grass to
the right , aft of the towplane. The glider is angled towards the runway

anf
rolls up onto the runway during the takeoff roll.

Jim

"Joseph L. Hyde" wrote in message
.. .
"BACK IN THE OLD DAYS" Hey I've flown planes recently using water
meth.....rolls dart and garretts.....oh wait that has been over 20

years
ago....never mind.....






"Jim Phoenix" wrote in message
...
Back in the old days water-meth worked pretty well, same basic effect.

I
think Metros still use it, at least they did 10 years ago. Handy in

the
Convair 580's as well - like, they needed more horsepower?

You just needed to be careful not to run out of water-meth at the

wrong
time.

Jim

"Jason Payne" wrote in message
...
Just a thought. Wanted to see what you guys thought. I know that

FAA
aproval would never happen, but seems like a good idea to me.

You could easily and safely run a 100hp shot of NO2 for the first

10-15
seconds of a takeoff roll in an 0-470 or similar motor, and get to

100
feet
and 65 knots a lot quicker than without, increasing safety margins.

NO2 is especially nice in a heat soaked motor because the shot cools

the
intake air a good 30-50 degrees...

From being in a ASH-25 at a full 750 kilos on a hot Uvalde day that
another
100 hp would really help getting off the ground if you are not

behind
a
big
motor like Scratch.









  #7  
Old March 7th 04, 09:43 PM
Mike Lindsay
external usenet poster
 
Posts: n/a
Default

In article , Bill Daniels
writes
OK, I guess this is a top post thread.

It ain't horsepower, it's the PROP. To improve the 0 - 20 acceleration,
improve the propeller. Have you ever tried to figure out how much power
actually gets to the tow hook on the glider from a 260 HP Pawnee? Maybe 20
HP?

At low speeds, as at the beginning of the TO roll, the tug's prop is mostly
stalled and converting little of the engines HP to thrust. As it
accelerates, more of the prop disc becomes unstalled and the prop picks up
efficiency and therefore more acceleration. A headwind helps a lot here.

So, what to do?

1. A constant speed prop reduces the blade AOA and lets the engine rev to
its redline RPM. (Noisy)
2. Big, slow turning props make much more thrust at low speeds than small,
high RPM props. (Quieter but require PRSU gearbox)
3. Ducted fans work really well at low speeds but lose out to a standard
prop at 100 MPH +. (A LOT quieter)

The ducted fan looks very good in that it can turn at crankshaft RPM while
producing several times the thrust of an unshrouded prop at zero airspeed.

So, why don't you folks living in a country blessed with friendly regulators
design and build a certified ducted fan tug using the minimum engine
necessary - say a 140 HP LOM M132CE. (Less fuel, less noise).
See: http://www.moraviation.com/

I imagine an airframe that looks somewhat like an Ogar. A cute trick would
be to make the fan and duct as one rotating unit constructed of carbon
fiber - this eliminates the problem of fan tip-duct clearance.

Bill Daniels


Something like that was developed here in the UK a few years ago.
It was a place STOL with a ducted fan and it could fly very slowly.
It was called the Optima and it was designed by a Mr Edgerly, who also
designed a sailplane, using unconventional materials.

Several examples were completed, more were under construction, but were
destroyed in a fire.

And isn't nitrous oxide N2O, not NO2 which is nitrogen dioxide?



--
Mike Lindsay
  #8  
Old March 8th 04, 11:02 PM
Mark James Boyd
external usenet poster
 
Posts: n/a
Default

Bill Daniels wrote:
OK, I guess this is a top post thread.

It ain't horsepower, it's the PROP. To improve the 0 - 20 acceleration,
improve the propeller. Have you ever tried to figure out how much power
actually gets to the tow hook on the glider from a 260 HP Pawnee? Maybe 20
HP?

At low speeds, as at the beginning of the TO roll, the tug's prop is mostly
stalled and converting little of the engines HP to thrust. As it
accelerates, more of the prop disc becomes unstalled and the prop picks up
efficiency and therefore more acceleration. A headwind helps a lot here.

So, what to do?

1. A constant speed prop reduces the blade AOA and lets the engine rev to
its redline RPM. (Noisy)
2. Big, slow turning props make much more thrust at low speeds than small,
high RPM props. (Quieter but require PRSU gearbox)
3. Ducted fans work really well at low speeds but lose out to a standard
prop at 100 MPH +. (A LOT quieter)

The ducted fan looks very good in that it can turn at crankshaft RPM while
producing several times the thrust of an unshrouded prop at zero airspeed.


Great stuff, Bill. I hadn't thought before how a headwind
helps a fixed pitch prop on the ground. Interesting...

I'm still excited about turbines on self-launch gliders
(and small planes). I was disappointed to learn that
Avemco puts turbines, no matter how small, in
a different insurance category than regular ol' planes.
It turns out my insurance only covers borrowed aircraft
with one or less engines, six or less seats, and
non-turbine without floats.

So much for the twin turbine Sparrowhawk ;(
--

------------+
Mark Boyd
Avenal, California, USA
  #9  
Old March 10th 04, 10:16 AM
Robert Ehrlich
external usenet poster
 
Posts: n/a
Default

Bill Daniels wrote:
...
1. A constant speed prop reduces the blade AOA and lets the engine rev to
its redline RPM. (Noisy)
2. Big, slow turning props make much more thrust at low speeds than small,
high RPM props. (Quieter but require PRSU gearbox)


Both constant speed and low RPM through an appropriate gearbox are
provided in the Super Dimona we use as tow plane. The noise is noticeably
lower than with a conventional prop, although the prop is of slightly
lower diameter than most of them. The noise reduction was sufficiently
significative that we got some help from the general fundings for
noise reduction. If we didn't had a lot of problems with the engine,
this would seem a very good solution.
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Parachute fails to save SR-22 Capt.Doug Piloting 72 February 10th 05 05:14 AM
Aviation crash videos on-line Dudley Henriques Piloting 113 September 12th 04 08:54 PM
The Internet public meeting on National Air Tour Standards begins Feb. 23 at 9 a.m. Larry Dighera Piloting 0 February 22nd 04 03:58 PM
SSA to Safety Group at Convention: "Clear Off!" ? SoarPoint Soaring 11 February 13th 04 04:48 PM
USAF = US Amphetamine Fools RT Military Aviation 104 September 25th 03 03:17 PM


All times are GMT +1. The time now is 03:59 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AviationBanter.
The comments are property of their posters.