Have there been any successful tip-jet helicopters?

[Jeremy Thomson]

I'm not aware of any tip-jet helicopters that have made it into
production.
Please correct me if I'm wrong.

At first the idea seems a no-brainer, no torque to counter, no
gearbox, should result in a lighter & thus more efficient aircraft.
I suppose the devil is in the details.
Is the problem with tip-jets the rotor hub?
Either you have to pass fuel or hot gas through the rotor hub to the
blades.
I guess sealing a rotating assembly with hot gases flowing through may
be a non-trivial problem?
But that shouldnt be a problem for jets-at-the-tips type designs, fuel
would not be hot enough to damage seals.
Perhaps there is a inherant flaw in the jets-at-the-tips style design?

I've seen videos of the Hughes heavy lift helicopter that directed the
output of a couple of turbojets(/fans ?) through the blades.
I thought that design was successful, it was more a matter of funding
that it wasnt put into production, am I wrong?

Jeremy Thomson

[Phil Miller]

On 23 Jul 2003 20:40:11 -0700, (Jeremy Thomson)
wrote:

>I'm not aware of any tip-jet helicopters that have made it into
>production.
>Please correct me if I'm wrong.

Didn't go into production, but an interesting read nonetheless
http://www.asra.org.au/rotordyn.htm

Some other stuff I found via Google
http://www.calpoly.edu/~wpatters/helo.html
and
http://avia.russian.ee/vertigo/hiller_crane-r.html
and
http://avia.russian.ee/vertigo/hiller_hj-1-r.html
and
http://www.germanvtol.com/wnffolder/sidewnf.html

I know a guy that is building one of these
http://www.rqriley.com/gluharef.html


Phil
--
Pfft...english! Who needs that? I'm never going to England.
Homer J. Simpson

[Scott Gardner]

I can't say it was successful in terms of production, but I did see it fly.

Go to: http://www.intora-firebird.com/main.htm

Scooter

"Jeremy Thomson" > wrote in message
m...
> I'm not aware of any tip-jet helicopters that have made it into
> production.
> Please correct me if I'm wrong.
>
> At first the idea seems a no-brainer, no torque to counter, no
> gearbox, should result in a lighter & thus more efficient aircraft.
> I suppose the devil is in the details.
> Is the problem with tip-jets the rotor hub?
> Either you have to pass fuel or hot gas through the rotor hub to the
> blades.
> I guess sealing a rotating assembly with hot gases flowing through may
> be a non-trivial problem?
> But that shouldnt be a problem for jets-at-the-tips type designs, fuel
> would not be hot enough to damage seals.
> Perhaps there is a inherant flaw in the jets-at-the-tips style design?
>
> I've seen videos of the Hughes heavy lift helicopter that directed the
> output of a couple of turbojets(/fans ?) through the blades.
> I thought that design was successful, it was more a matter of funding
> that it wasnt put into production, am I wrong?
>
> Jeremy Thomson

[Brantly Nuts]

There have been at least 2 tip-jet type helicopters to reach type
certification and production.

Sud Ouest So.1221 Djinn, about 150 produced.
http://avia.russian.ee/vertigo/snias_jinn-r.html

Kolibri H-3, about 10 produced.
http://avia.russian.ee/vertigo/nhi_kolibri-r.html


(Jeremy Thomson) wrote in message >...
> I'm not aware of any tip-jet helicopters that have made it into
> production.
> Please correct me if I'm wrong.
>
> At first the idea seems a no-brainer, no torque to counter, no
> gearbox, should result in a lighter & thus more efficient aircraft.
> I suppose the devil is in the details.
> Is the problem with tip-jets the rotor hub?
> Either you have to pass fuel or hot gas through the rotor hub to the
> blades.
> I guess sealing a rotating assembly with hot gases flowing through may
> be a non-trivial problem?
> But that shouldnt be a problem for jets-at-the-tips type designs, fuel
> would not be hot enough to damage seals.
> Perhaps there is a inherant flaw in the jets-at-the-tips style design?
>
> I've seen videos of the Hughes heavy lift helicopter that directed the
> output of a couple of turbojets(/fans ?) through the blades.
> I thought that design was successful, it was more a matter of funding
> that it wasnt put into production, am I wrong?
>
> Jeremy Thomson

[Rocky]

(Jeremy Thomson) wrote in message >...
> I'm not aware of any tip-jet helicopters that have made it into
> production.
> Please correct me if I'm wrong.

The french had one in the 60's called a Djin. I saw one flying in
South Africa where they were trying to adapt it for agricultural
flying in the Cape Province. It was never very popular nor successful.
>
> At first the idea seems a no-brainer, no torque to counter, no
> gearbox, should result in a lighter & thus more efficient aircraft.
> I suppose the devil is in the details.
> Is the problem with tip-jets the rotor hub?
> Either you have to pass fuel or hot gas through the rotor hub to the
> blades.
> I guess sealing a rotating assembly with hot gases flowing through may
> be a non-trivial problem?
> But that shouldnt be a problem for jets-at-the-tips type designs, fuel
> would not be hot enough to damage seals.
> Perhaps there is a inherant flaw in the jets-at-the-tips style design?
>
> I've seen videos of the Hughes heavy lift helicopter that directed the
> output of a couple of turbojets(/fans ?) through the blades.
> I thought that design was successful, it was more a matter of funding
> that it wasnt put into production, am I wrong?
>
> Jeremy Thomson

[terra]

David Lednicer wrote:

> The Sud-Ouest SO 1221 Djinn was the only one that was at all succesful.
> The US Army evaluated three as the YHO-1.
>
> See: http://www.helis.com/timeline/aerospatiale.php

Did *you* click the link to see the Djinn? With your Netscape 7.02?
Using 7.1, almost every link gets me a popup box telling me I need Netscape 4 or
higher. Duh.

[terra]

Brantly Nuts wrote:

> There have been at least 2 tip-jet type helicopters to reach type
> certification and production.
>
> Sud Ouest So.1221 Djinn, about 150 produced.
> http://avia.russian.ee/vertigo/snias_jinn-r.html
>
> Kolibri H-3, about 10 produced.
> http://avia.russian.ee/vertigo/nhi_kolibri-r.html

It says version #1 "was written off through ground resonance". Maybe due to
something like a fuel imbalance through the blades, because 2-blade rotors don't
suffer from ground resonance. Do they?

[ops]

Jeremy Thomson wrote:
> I'm not aware of any tip-jet helicopters that have made it into
> production.
> Please correct me if I'm wrong.
>
>



Where does the Hiller YH-32 fit in then?

http://www.museumofflight.org/collections/craftdisplay.html?ID=59

http://avia.russian.ee/vertigo/hiller_hoe-1-r.html


rm

[David Lednicer]

I got this when I tried to view it with Netscape 7.02, so I switched and
tried IE 6.0 and it worked.

[Sla#s]

"Rocky" > wrote in message
om...
> (Jeremy Thomson) wrote in message
>...
> > I'm not aware of any tip-jet helicopters that have made it into
> > production.
> > Please correct me if I'm wrong.
>
> The french had one in the 60's called a Djin. I saw one flying in
> South Africa where they were trying to adapt it for agricultural
> flying in the Cape Province. It was never very popular nor successful.

The Djiin was a very successful crop spraying aircraft in the UK and France.
During the sixties and early seventies a group of them from the company
SEPATOM (I think) started the year working their way up from the south of
France spraying vines with Bordeaux mixture. Then they came to the UK and
sprayed the potatoes in Lincolnshire and Lancashire with Maneb.
About '72 BEAS Helicopters, Oxford, bought eight of them and used them for a
good few years before they switched to Bell 47s. They were cheap to run and
easy to fly but eventually shortage of spares grounded them.
Starting them was great fun, if you were fit. They had a great big handle
out the side to wind up the turbine! No electric start you see, in fact no
electric's!

Slatts

[Ken Sandyeggo]

(Jeremy Thomson) wrote in message >...
> I'm not aware of any tip-jet helicopters that have made it into
> production.
> Please correct me if I'm wrong.
>
> At first the idea seems a no-brainer, no torque to counter, no
> gearbox, should result in a lighter & thus more efficient aircraft.
> I suppose the devil is in the details.
> Is the problem with tip-jets the rotor hub?
> Either you have to pass fuel or hot gas through the rotor hub to the
> blades.
> I guess sealing a rotating assembly with hot gases flowing through may
> be a non-trivial problem?
> But that shouldnt be a problem for jets-at-the-tips type designs, fuel
> would not be hot enough to damage seals.
> Perhaps there is a inherant flaw in the jets-at-the-tips style design?
>
> I've seen videos of the Hughes heavy lift helicopter that directed the
> output of a couple of turbojets(/fans ?) through the blades.
> I thought that design was successful, it was more a matter of funding
> that it wasnt put into production, am I wrong?
>
> Jeremy Thomson

I think that the general concensus is that they all proved extremely
noisy and consumed an inordinate quantity of fuel, 2 factors that have
limited their success and further development.

Ken J. - Sandie A. Geaux

[terra]

David Lednicer wrote:
> I got this when I tried to view it with Netscape 7.02, so I switched and
> tried IE 6.0 and it worked.

Ah, another IE-only page. The site is busted, it relies on out-of-date javascript.

I viewed the Sud-Ouest SO.1221 Djinn at
http://avia.russian.ee/vertigo/snias_jinn-r.html (thanks, Brantly Nut), and
deleted my helis.com bookmark.

[jorge]

terra > wrote in message >...
> David Lednicer wrote:
> > I got this when I tried to view it with Netscape 7.02, so I switched and
> > tried IE 6.0 and it worked.
>
> Ah, another IE-only page. The site is busted, it relies on out-of-date javascript.
>
> I viewed the Sud-Ouest SO.1221 Djinn at
> http://avia.russian.ee/vertigo/snias_jinn-r.html (thanks, Brantly Nut), and
> deleted my helis.com bookmark.

I didnt know this group was for rating sites ! :-)
Is not my fault if netscape versions are not backwards compatibles,
anyway, I just download, install and review NS7 and update the
scripts.
Hope its works fine now

[terra]

jorge wrote:
> terra > wrote in message >...
>> David Lednicer wrote:
>> > I got this when I tried to view it with Netscape 7.02, so I switched and
>> > tried IE 6.0 and it worked.
>>
>> Ah, another IE-only page. The site is busted, it relies on out-of-date javascript.
>>
>> I viewed the Sud-Ouest SO.1221 Djinn at
>> http://avia.russian.ee/vertigo/snias_jinn-r.html (thanks, Brantly Nut), and
>> deleted my helis.com bookmark.
>
> I didnt know this group was for rating sites ! :-)

It's for bashing IE-only sites. If the trend continues, the web will be
accessible not just to IE users only, but to *Windows* users only. No Mac, and
no Linux.

> Is not my fault if netscape versions are not backwards compatibles,

I don't know what you're saying here. Your script looked for Netscapes 4 and 6,
no awareness of 7.
So I fired up Netscape 4.79... and... the page didn't load at all! Nothing.
After I disabled Stylesheets it loaded, but then the links didn't work.

> anyway, I just download, install and review NS7 and update the
> scripts.
> Hope its works fine now

Thank you! It works in 7, but not old 4.79, which is good enough.

BTW, AOL has recently closed up the Netscape shop, the company is out of
business, so you won't have to look for a Netscape 8 :-(
But... development on Mozilla continues :-)
It's the "same" browser, without the Netscape name in the identifier. There's a
family of other browsers also based on Mozilla: K-Meleon, Beonex, Firebird, IBM
Browser, etc. And then there's Opera. Will your site work with those? I think
the javascript is a bad idea.

[Rod Buck]

In message >, terra
> writes
>David Lednicer wrote:
>> I got this when I tried to view it with Netscape 7.02, so I switched and
>> tried IE 6.0 and it worked.
>
>Ah, another IE-only page. The site is busted, it relies on out-of-date
>javascript.

More likely that Netscape is busted, as it's riddled with
non-html4-compliant errors.


--
Rod Buck

[terra]

Rod Buck wrote:

> In message >, terra
> > writes
>>David Lednicer wrote:
>>> I got this when I tried to view it with Netscape 7.02, so I switched and
>>> tried IE 6.0 and it worked.
>>
>>Ah, another IE-only page. The site is busted, it relies on out-of-date
>>javascript.
>
> More likely that Netscape is busted, as it's riddled with
> non-html4-compliant errors.

No, Netscape 7 is the most standards-compliant browser out there by a long
stretch, as in 100% compliant. You're thinking of Netscape 4.

If you want to see a busted browser, go to
http://www.meyerweb.com/eric/css/edge/complexspiral/demo.html with IE.
Or try any of the other demos listed at
http://www.meyerweb.com/eric/css/edge/index.html

[Rod Buck]

>
>No, Netscape 7 is the most standards-compliant browser out there by a long
>stretch, as in 100% compliant. You're thinking of Netscape 4.
>
>If you want to see a busted browser, go to
>http://www.meyerweb.com/eric/css/edge/complexspiral/demo.html with IE.
>Or try any of the other demos listed at
>http://www.meyerweb.com/eric/css/edge/index.html
>
True Netscape 4 was garbage, but I have little experience of Netscape 7
- didn't want to waste time finding out....




--
Rod Buck

[terra]

Rod Buck wrote:

>>
>>No, Netscape 7 is the most standards-compliant browser out there by a long
>>stretch, as in 100% compliant. You're thinking of Netscape 4.
>>
>>If you want to see a busted browser, go to
>>http://www.meyerweb.com/eric/css/edge/complexspiral/demo.html with IE.
>>Or try any of the other demos listed at
>>http://www.meyerweb.com/eric/css/edge/index.html
>>
> True Netscape 4 was garbage, but I have little experience of Netscape 7
> - didn't want to waste time finding out....

You certainly shouldn't risk finding anything out.

[Dan & Jan Hollenbaugh]

Ken's right - tip jet designs seem like a great idea - no transmission,
minimal antitorque (you still have a small amount of friction torque and you
have to have some form of yaw control) - but tip jet drive is incredibly
inefficient. I researched these a number of years ago, as a young engineer.
I remember a quote about the YH-32, to the effect that its major success was
it's ability to turn fuel into noise.

Dan Hollenbaugh

Ken Sandyeggo wrote in message
>...
>
>I think that the general concensus is that they all proved extremely
>noisy and consumed an inordinate quantity of fuel, 2 factors that have
>limited their success and further development.
>
>Ken J. - Sandie A. Geaux

[Sla#s]

"Dan & Jan Hollenbaugh" > wrote in message
...
> Ken's right - tip jet designs seem like a great idea - no transmission,
> minimal antitorque (you still have a small amount of friction torque and
you
> have to have some form of yaw control) - but tip jet drive is incredibly
> inefficient. I researched these a number of years ago, as a young
engineer.
> I remember a quote about the YH-32, to the effect that its major success
was
> it's ability to turn fuel into noise.

The reason the British Rotordyne was finally scraped was because of the
noise problem.
Unfortunately government committees work so slowly that the problem was
almost solved before they finally scrapped it!
So it is possible to quieten tip jets down. I believe they did it by
changing the original round exits into long trailing edge slots.
http://www.asra.org.au/rotordyn.htm

Slatts