Hyabusa flat 8

Brian Whatcott wrote:

Oh yes, they tend to run them on natural gas. That's quite a favorable
factor, apparently.

I have to ask: why?


--
BMW K1100LT Ducati 750SS Honda CB400F SH50
If you don't know what you're doing, don't do it. Workshop manual?
Buy one instead of asking where the free PDFs are
chateau dot murray at idnet dot com

Brian Whatcott wrote:

TOG@Toil wrote:
... I mean, what was max revs for a Merlin?

Googles

Hm. About 3000rpm. Just off tickover for a 'Busa.

I THINK that was the prop shaft - like many other aero recips
it's limited by 0.9 c at the prop tips at the top end of the tach.

Didn't the Harvard's prop tips go supersonic?

But the crank was driven by pistons breathing gas though a duplex
compressor system - driving a PRU.
Then again - in War mode its overhaul time was measured
in the hours you can count on one to two hands.
Low compression heads on the Merlin
were the choice for civil airliners post war.

Hm. Makes sense. That said, Merlins were hardly used in 'proper' civil
aircraft. The York and the Lancastrian, of course, both of which were
Lancaster variants. And the Tudor, which was a failure.

Can't think of any others, though I'd be delighted to be informed. Most
of the piston-engined civil airliners I can think of used air-cooled
radial engines.


--
BMW K1100LT Ducati 750SS Honda CB400F SH50
If you don't know what you're doing, don't do it. Workshop manual?
Buy one instead of asking where the free PDFs are
chateau dot murray at idnet dot com

The Older Gentleman wrote:
Brian Whatcott wrote:

Oh yes, they tend to run them on natural gas. That's quite a favorable
factor, apparently.

I have to ask: why?



I don't have the definitive answer - but here's my guess.
Those pump engines tend to be carbureted, and atomizing the gas at high
throttle would be an issue. Burning dirty is not good for engines.
(One reason why fuel injected engines with ECUs in cars tend to go 100K
easily these days)
Natural gas gets you 100% atomization out of the box.

Brian W

The Older Gentleman wrote:
... - like many other aero recips
it's limited by 0.9 c at the prop tips at the top end of the tach.

Didn't the Harvard's prop tips go supersonic?

....
Low compression heads on the Merlin
were the choice for civil airliners post war.

Hm. Makes sense. That said, Merlins were hardly used in 'proper' civil
aircraft. The York and the Lancastrian, of course, both of which were
Lancaster variants. And the Tudor, which was a failure.

Can't think of any others, though I'd be delighted to be informed. Most
of the piston-engined civil airliners I can think of used air-cooled
radial engines.


Here's Wiki's idea of the direct uses: not to mention tanks, boats, and
a car (!)

* Armstrong Whitworth Whitley
* Avro Lancaster
* Avro Lincoln
* Avro Tudor
* Avro York
* Boulton Paul Defiant
* Bristol Beaufighter
* Curtis P-40 Kittyhawk
* de Havilland Mosquito
* de Havilland Hornet
* Fairey Barracuda
* Fairey Battle
* Fairey Fulmar
* Handley Page Halifax
* Hawker Hurricane and Sea Hurricane
* Hispano Aviación HA-1112
* North American Mustang X
* Short Sturgeon
* Supermarine Seafire
* Supermarine Spitfire
* Vickers Wellington
* Westland Welkin

Aircraft with sonic tips have a noisy bark....

Brian W

"Brian Whatcott" wrote in message
...
The Older Gentleman wrote:
Brian Whatcott wrote:

Oh yes, they tend to run them on natural gas. That's quite a favorable
factor, apparently.

I have to ask: why?



I don't have the definitive answer - but here's my guess.
Those pump engines tend to be carbureted, and atomizing the gas at high
throttle would be an issue. Burning dirty is not good for engines.
(One reason why fuel injected engines with ECUs in cars tend to go 100K
easily these days)
Natural gas gets you 100% atomization out of the box.

Brian W

That is most likely the reason. We used to run a standby generator on
propane, and never saw any unburned carbon buildup in the oil. So I would
expect natural gas to be at least as good.

Peter

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember bildan saying
something like:

Keep in mind how the motorcycle works. *The bike has a 6-speed gearbox
whereas the airplane engine would have only one. *The standard sport
bike shift technique, approved by the factory, is to apply a large
force to the shift lever and then tap the clutch lever when the rider
wants to shift.

I don't think it is, you know. ISTBC of course.

Some people just like rebuilding gearboxes.

Nope, "pre-load and clutch" is how Sport Bike constant mesh,
progressive transmissions are DESIGNED to be shifted. It just shows
how much abuse these engines and transmission are intended to take.

You really don't have a ****ing clue, do you?

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember (The
Older Gentleman) saying something like:

Brian Whatcott wrote:

Oh yes, they tend to run them on natural gas. That's quite a favorable
factor, apparently.

I have to ask: why?

It's a very clean-burning fuel and the oil lasts for ages, or more
accurately, keeps hold of its properties a fair bit longer than oil
that's steadily getting mankier and mankier in a petrol engine.

Grimly Curmudgeon wrote:

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember (The
Older Gentleman) saying something like:

Brian Whatcott wrote:

Oh yes, they tend to run them on natural gas. That's quite a favorable
factor, apparently.

I have to ask: why?

It's a very clean-burning fuel and the oil lasts for ages, or more
accurately, keeps hold of its properties a fair bit longer than oil
that's steadily getting mankier and mankier in a petrol engine.

Thanks all. Very interesting. I knew they were clean engines, but never
thought or the aircraft application.


--
BMW K1100LT Ducati 750SS Honda CB400F SH50
If you don't know what you're doing, don't do it. Workshop manual?
Buy one instead of asking where the free PDFs are
chateau dot murray at idnet dot com

Brian Whatcott wrote:

Hm. Makes sense. That said, Merlins were hardly used in 'proper' civil
aircraft. The York and the Lancastrian, of course, both of which were
Lancaster variants. And the Tudor, which was a failure.

Can't think of any others, though I'd be delighted to be informed. Most
of the piston-engined civil airliners I can think of used air-cooled
radial engines.


Here's Wiki's idea of the direct uses: not to mention tanks, boats, and
a car (!)

* Armstrong Whitworth Whitley
* Avro Lancaster
* Avro Lincoln
* Avro Tudor
* Avro York
* Boulton Paul Defiant
* Bristol Beaufighter
* Curtis P-40 Kittyhawk
* de Havilland Mosquito
* de Havilland Hornet
* Fairey Barracuda
* Fairey Battle
* Fairey Fulmar
* Handley Page Halifax
* Hawker Hurricane and Sea Hurricane
* Hispano Aviación HA-1112
* North American Mustang X
* Short Sturgeon
* Supermarine Seafire
* Supermarine Spitfire
* Vickers Wellington
* Westland Welkin

And how many of those were civil airliners, eh???

--
BMW K1100LT Ducati 750SS Honda CB400F SH50
If you don't know what you're doing, don't do it. Workshop manual?
Buy one instead of asking where the free PDFs are
chateau dot murray at idnet dot com

On Fri, 6 Mar 2009 18:32:24 -0600, "Maxwell" #$$9#@%%%.^^^ wrote:


"Ace" wrote in message
.. .
On Fri, 6 Mar 2009 13:11:32 -0600, "Maxwell" #$$9#@%%%.^^^ wrote:


"platypus" wrote in message
. com...

The thing that everyone seems to forget when promoting automotive
engines
for aircraft is that most piston aero engines have a very hard life.
Take-off and climb is full power or very nearly, then they throttle back
to cruise at 75% or thereabouts. The only roadgoing vehicles that
approach that sort of use are in motorsports, and how long do they last?


Not true at all.

I drove a 6500
series Chevy dump truck years ago, always pulling a Case 580C back hoe. It
was 100% power almost all the time, and always at lease 75% on the
highway.

But that;s true of nearly all agricultural vehicles, which is why they
tend to use understressed, low-revving, low-tech motors. And just
because you can drive them on the road doesn't make the road-going
vehicles.


These were not ag vehicles. Passenger car engines were popular back then in
all the class C motor homes, school buses, and light weight dump trucks. My
Chevy was a 350-2v with probably nothing more than the heavy duty 4 bolt
main block. It also had a 4 speed manual transmission, and 2 speed rear. I
would commonly shift the low gears as high a 4000-5000 rpm. The gross weight
on the entire package was around 30,000 lbs.

The 2bbl 350 wasn't even a 4 bolt block. Only "select" 4 barrel
engines were 4 bolt.
The small block 400 also was USUALLY not 4 bolt.
396 and 454 were common RV (and truck) engines, along with the 402.
In heavier trucks you were more likely to get "real truck" engines
like the 366 etc.

Chrysler put a LOT of 413 and 440 engines in medium duty trucks (like
dump trucks etc) over the years - and used the same engines in New
Yorkers and Imperials, as well as road runners etc (440).

Ford did the same with the 460. Standard engine in big Lincolns,
optional in pickups and LTDs, and very common in 3-10 ton trucks as
well.