2 stroke thread (with occasional F1 relevance!)

[autogyro]

If you want real performance, Dominator gyro two seat
http://youtu.be/2UPPSyf5QAU

Not bad.
Not far off the performance of a W116 ts but with twice the power and only one person.

[autogyro]

Or, what about a rotary piston mill for your rotary wing aircraft?
These shown below are diminutive wee things..
..but maybe a 20B triple rotor Toyo Kogyo would give it a kick up the jacksey..
..if a running a bit thirsty, just like VW & Subaru boxer 4S..
http://www.uavenginesltd.co.uk/products/

There was a Norton rotary powered Wallis W116 with a great performance.
The engine was supplied by Norton shortly before the Japanese prevented the company from racing their engine in motor cycle racing and wiping the board.
Another scandal of the motor sport corrupt world.
The wankel worked well in the Wallis but just like the many two strokes tried its rpm where to high and gearing it down gave vibration problems a short service life and an engine that felt like it was stuck in bottom gear.
For light aircraft NASA should stick to spy satellites, the old 1930s engines still in use in most light aircraft meet the requirement far better than the high powered designs that only work well for aerobatics and air show use.
You guys with the two strokes should try flying a light AG or aircraft for over 8 hours solid before you sign off a noisy high reving head ache maker. They drive you nuts when trying to undertake a difficult operational task and give your position away from 10 miles.

[J.A.W.]

Ah yeah, A-G, the forum & topic are in fact - about noisy high-performance motorsport..

Not that the military has been too concerned about how loud their engines are, historically..
From WW1 tanks & planes to decades flying beastly Griffon engined Shacks, or even noisier Tu 95s..

I wear ear plugs when riding my loud 2-stroke motorcycles, or suffer tinnitus..
.. but that is muchly from wind noise, since if you are going fast, the engine sound is mostly behind you..

[autogyro]

So let us recap.
The Wallis W116 autogyro has a faster climb rate and a better over all performance than ANY other AG on a mere 60hp.
This is not just my statement but that of every skilled pilot who has flown the Wallis and there have been hundreds including top test pilots from all areas of aviation.

Evaluating the suitability of two strokes for F1 application and using the autogyro analogy could be useful.
Certainly the power to weight ratio is better for a two stroke everything else being equal but this is only one issue.
It is not just the engine that makes the machine and certain types of engine can detract from the over all capability.
Adrian Newey's recent results with this year Red Bull show just how close an F1 car's performance can be brought to that of the current leaders even with a major power deficit if there is a genius designing the whole package.
The Wallis W116 has a very special rotor head and rotor blade design that is far better than other types.
Compare this to Adrian's aerodynamic skills. (and the way daft regulations prevent future development FIA CAA)
Just giving an aircraft (or F1 car) more 'grunt' is not the answer and has been tried by many over the last 40 years without success.

As an aside, when Adrian Newey was awarded the Segrave Trophy at the RAC Club in 2010, Wing Commander Ken Wallis was there. Ken has won the trophy twice in the past along with Donald Campbell and a few other people who might be of interest. Of course these days such people tend to be ignored by the majority of the uneducated morons we now breed.

The Subaru flat four four stroke with water cooling and direct drive is the most suitable engine for light aircraft and AG use IMO. It has a proven production record is light can be cammed for slow running and direct drive. It can be turbocharged for altitude use maintaining a decent power curve and reasonably high output. It is also water cooled which is essential for reliable high altitude and world wide operational use.
There is a W116 with this engine but it is only a basic prototype.
Ken was over 90 years old when it was built and I was prevented from developing the Pro Drive turbocharged version of the engine that Pro Drive wanted to be built by Subaru.
Wallis has NEVER sold kit autogyros.
The W116 is a serious aviation system that has been fully proven in ALL its operational roles.

[autogyro]

Ah yeah, A-G, the forum & topic are in fact - about noisy high-performance motorsport..

Not that the military has been too concerned about how loud their engines are, historically..
From WW1 tanks & planes to decades flying beastly Griffon engined Shacks, or even noisier Tu 95s..

I wear ear plugs when riding my loud 2-stroke motorcycles, or suffer tinnitus..
.. but that is muchly from wind noise, since if you are going fast, the engine sound is mostly behind you..

For surveillance work it is essential to have an engine with as little noise as possible.
It was also useful for trips into East Germany to recover people, cant say much about that.
Of course if you just want to roar about in circles I would be pleased to stick a rocket where the Sun doesn't shine and light the touch paper.
At 500 feet the Wallis can hardly be heard, this is because the engine noise goes upwards with the airflow through the un-driven rotor. Unlike a helicopter that throws all the noise at the ground and disturbs the surface.
Over the desert at three feet up the Wallis is almost undetectable until it is on top of you.
No running to hide with five minutes grace as with a noisy overkill gunship.
I was on Nimrods and they could make far more noise than a Shack.

[J.A.W.]

Well A-G, regardless of your opinion regarding the efficacy of utilizing the Subaru car mill,
& while it may be for you, the best of a bad bunch, as NASA has noted, 2Ts are indeed superior..

It is of course, simply a matter of funding/producing the most suitable design..
..& rockets of the type you describe are not readily throttle-able for control purposes, let alone endurance..

Anyhow, A-G you do realize that F1 has long forbidden usage of modified production mills - right?
Wasn't it a Repco-Brabham - driven by Denny Hulme back in `67 - the last to win the W/Championship thusly?

[autogyro]

Like I originally alluded to, I have a two stroke concept (similar to Manolis) that might be of use for light aviation.
I will let you know if I ever get a chance to develop it.
Saying NASA knows about light aviation engines is a bit like saying Boeing knows about jet engines.
Its a contradiction in terms.

[J.A.W.]

Seems they do know a bit about it A-G, & interestingly they mention in their report.. ..a McCulloch TRAD-4180,
that looks suitable, & I wonder what Husqvarna, when they took over Mc C, did with it?
Read here.. http://www.ntrs.nasa.gov/archive/nasa/c ... 011788.pdf

[autogyro]

Seems they do know a bit about it A-G, & interestingly they mention in their report.. ..a McCulloch TRAD-4180,
that looks suitable, & I wonder what Husqvarna, when they took over Mc C, did with it?
Read here.. http://www.ntrs.nasa.gov/archive/nasa/c ... 011788.pdf

I think I have seen parts of this report before.
I will check through my paperwork.
I cant remember if these were taken from the old Napier development papers or those I have copies of from Bristols.
You should get yourself some data on the Rolls Royce Crecy it is certainly later in technology than this paper.
There was a diesel version of the Crecy projected before compound engines with turbines stopped the development of pure reciprocating types.
However a sleeve valved supercharged through scavenged engine of this type would be to complex and heavy for a light aircraft application much as the Jumo opposed piston engine was.
NASA are 50 years behind the times on this.

[uniflow]

I don't believe I'm having this conversation, trying to compare a 1930's push rod fourstroke to a modern twostroke. There is no comparison. I manufacture Autogyros (Dominators under licence) and manufacture engines both two and four stroke. The twostroke is by far the best in terms of power to weight, simplest to build and with EFI would be the most efficent. This is the modern world, there is no place for air cooled pushrod engines any more. Hey why not try a flat head you might find these engines even smoother and quieter. Efficency counts these days and you will find that combustion chamber in your 1930's engine is far from ideal
Two more facts, an American gyro has the record for max height at somthing like 33000 feet
This two seat gyro you see performing on youtube will climb at just on 2000 fpm, not trading speed for hight like the gyro in your video and the best bit, you can actualy buy a kit and build one your self.
Rant over.

[J.A.W.]

NASA are 50 years behind the times on this.[/quote]


Actually A-G, if you care to check the facts - viz read the ~20yo NASA report which details the Garrett ICE helicopter
mill study ( high efficiency 2T turbo-compound-diesel good for 2.2Ltr/1000hp), you will have to concede that
U-F, is of course - quite correct - in his emphatic assertions..

[uniflow]

J.A.W, thank you.

[J.A.W.]

Here is another ( current) example of a smooth running 2-stroke aero-mill..

http://www.zoche.de/

[autogyro]

I don't believe I'm having this conversation, trying to compare a 1930's push rod fourstroke to a modern twostroke. There is no comparison. I manufacture Autogyros (Dominators under licence) and manufacture engines both two and four stroke. The twostroke is by far the best in terms of power to weight, simplest to build and with EFI would be the most efficent. This is the modern world, there is no place for air cooled pushrod engines any more. Hey why not try a flat head you might find these engines even smoother and quieter. Efficency counts these days and you will find that combustion chamber in your 1930's engine is far from ideal
Two more facts, an American gyro has the record for max height at somthing like 33000 feet
This two seat gyro you see performing on youtube will climb at just on 2000 fpm, not trading speed for hight like the gyro in your video and the best bit, you can actualy buy a kit and build one your self.
Rant over.

I could only see one person in the twin seater Dominator video you posted that is a fair bit of climb for weight trading.
The Wallis two seater shown had a 'heavy' passenger and was fully capable of operational tasking on ONLY 60hp.
Can I see a video of your Dominator with two up flying on 60hp please?
Will it actually get airborne on that power with such a basic rotor head?
Have you achieved a Full Certificate of Airworthiness for your Dominator or do you fly them on a 'permits to fly'?
The current world altitude record for light autogyros was achieved using a turbocharged engine.
The Wallis has achieved all its records past and present without any form of supercharging.
The only reason the Wallis lost the altitude record was because Ken was over 90 years old.
He was getting ready for a new speed record when he died at 97 he was still flying.
Start believing you are having this conversation, you will be having it for the next 40 years until you gain the same experience that Wallis had.
There was a prototype W116 with a cross configured supercharged two stroke of over 130 hp.
This was an Italian engine and proved unreliable and too noisy for proper operational use.
OK for fun flying in a kit AG perhaps much like all the modern two stroke engines available today.

[autogyro]

Actually A-G, if you care to check the facts - viz read the ~20yo NASA report which details the Garrett ICE helicopter
mill study ( high efficiency 2T turbo-compound-diesel good for 2.2Ltr/1000hp), you will have to concede that
U-F, is of course - quite correct - in his emphatic assertions..

Of course he is correct the data he used was also correct.
However outright power to weight is not the main issue with a light aircraft engine.
Turbo compounds of 2.2 litres per 1000hp are hardly worth considering.