XP-65/F7F Development

[pinsog]

Pinsog, your point is well taken, and I apologise. As Fubar says, we have a history with our Zipper, and sometimes go a little over the top in dealing with his questions. Thanks for calling me on it. I was out of line.
Cheers,
Wes

Thank you sir. We can all get annoyed sometimes. Have a good day.

 

[wuzak]

I don't know the exact date "pay-as-you-go" was initiated but I do know that the R-4360 the first engine project to use it. Also with this system all IP rights were transferred to the military. At least as far as manufacturing right were concerned.

Is that true?

I thought that the R-4360 was a private venture that was supported by the military.

 

[Jugman]

Initially it was but Congress didn't like the idea of the services footing the r&d bill and industry reaping the rewards.

As the system worked in the UK prewar and during the war, it was next to impossible to lose money on R&D once government funding was secured. So they weren't completely out of line.

But like I said I'm not sure exactly how much IP was given away. White says all of it but he doesn't say if P&W retained any rights to it.

 

[pbehn]

Initially it was but Congress didn't like the idea of the services footing the r&d bill and industry reaping the rewards.

As the system worked in the UK prewar and during the war, it was next to impossible to lose money on R&D once government funding was secured. So they weren't completely out of line.

But like I said I'm not sure exactly how much IP was given away. White says all of it but he doesn't say if P&W retained any rights to it.

If you read the history of Frank Whittle and the UK development of jet engines it is almost impossible to tell the difference between state and private investment and while USA spending on the military was higher than the UKs the percentage of state spending was much higher in UK, in the UK during the war the government controlled everything. Whittle worked for the RAF but had to form a company whos only possible clients were the government.

 

[Peter Gunn]

*SNIP*

Instead of us spoon feeding it to you;
Superchargers

Excellent link, the pictures alone are a treasure, I love when a project is well documented photographically. Thanks again.

 

[pinsog]

Instead of us spoon feeding it to you;
Superchargers[/QUOTE]

Cool article. Love the pics. I bet the driver was wishing that old truck was turbocharged before he got to the top of Pikes Peak!!! (Truck running wide open, in gear as driver walks beside it smoking a cigarette)

 

[Zipper730]

Yes Zipper, but that is not true science. You can run an engine at 10,000 ft up a mountain but what does that tell you?

During early testing it would give a basic idea of what the engine would do at different altitude if there were an inadequate number of test-celles

The trick is to find out what you can discover from a test like a single cylinder prototype and what you cant.

Stanley Hooker who made big strides in the development of supercharger for Rolls Royce also has this in his Wikipedia page,

"One major outcome of his work introduced a generalised method of predicting and comparing aircraft engine performance under flight conditions.

From what I read: He joined RR in 1937, started working on superchargers in 1938.

Going on "location" helped in 1918 but you still have a truck load of variables.

Good point

They had 15-22 years to develop climate controlled test labs right on the factory grounds after 1918 to help eliminate the variables and permit a test schedule that was more independent of the weather.

We had test cells available in 1933?

I don't know the exact date "pay-as-you-go" was initiated but I do know that the R-4360 the first engine project to use it.

Not sure when the design started but it might have been around 1942: It was first run in 1944...

Also with this system all IP rights were transferred to the military. At least as far as manufacturing right were concerned.

Did that change?

NACA wasn't setup to do, nor was it their mission to do the kind of work the army needed.

That's true, but...

• NACA's job was to develop the field of aerospace engineering and propulsion engineering
• Their work generally was based on coming up with new airfoil/airframe, new engineering and engine concepts: They did however test ideas out.

Sir, I would imagine Zipper is a younger person that doesn't have the experience or knowledge of the rest of the group.

I'm 34

Obviously he is interested and would like to learn

Correct

 

[pinsog]

Hello Zipper. I'm 47. I think many of these guys are retired and a lot of them are in the aerospace industry or ex military. I've learned tons myself. Listen to them, research on your own and ask questions on stuff you don't understand. Above all, enjoy yourself!!!! Have a great day

 

[Jugman]

Not sure when the design started but it might have been around 1942: It was first run in 1944...

The official start date for the R-4360 was in November 1940. Major funding came some time later.

Did that change?

It has been modified but I have no knowledge with regards to when or why.

That's true, but...

• NACA's job was to develop the field of aerospace engineering and propulsion engineering
• Their work generally was based on coming up with new airfoil/airframe, new engineering and engine concepts: They did however test ideas out.

NACA's job was to advance the theory of flight not to apply it to practical everyday problems. The army needed expertise in the latter. In any event NACA didn't have the kind of facilities to build an engine from scratch.

 

[pbehn]

During early testing it would give a basic idea of what the engine would do at different altitude if there were an inadequate number of test-celles
From what I read: He joined RR in 1937, started working on superchargers in 1938.

The real advantage of running a test up a mountain at 10,000ft is the ability to strap as many sensors on it as you can manage and record their readings. Thermocouples, thermometers, surface pyrometers, barometers, flow meters etc which cannot be done on an aircraft. This is how things work, the information learned will have been used to improved understanding of how engines work and what works at all altitudes.

Hooker was (as another poster pointed out) a mathematician who also studied hydro and fluid dynamics at university. He started working on the Merlin Supercharger initially in response to a request from the Air Ministry for a turbocharged Merlin to power a high altitude Wellington bomber/recon aircraft. His work or the Merlin supercharger initially produced the Merlin 45 and then the 61, but he was a mathematician and an engineer, his improvements to the Merlin were not from years of getting his hands dirty but really knowing the subject of compressing and moving gases in engines, which was equally applicable to jet engines.

The world was changing at a remarkable rate. In 1903 when the Wright Brothers first flew an airplane, Henry Ford also started his car company after leaving what would become Cadillac in the next decade engine production would have passed 1 million units.. You could say that the Wright brothers with their mechanic were the only proven experts in aviation engineering, only 15 years later at the end of the first world war there were more aviation companies and aircraft engine manufacturers than you could wave a stick at.

!903 was also the year that Stanford Moss wrote his thesis on turbo supercharging

 

[MiTasol]

Try talking to him like he's your grandson. Obviously he is interested and would like to learn, so let's be kind and teach him, enjoy the opportunity to pass on your knowledge. Remember that none of us was born knowing anything, we all had to learn 1 step at a time.

Right on!!

For the benefit of the many who do not understand the basics of engine design and its direct relationship to aircraft design I recommend reading the 1943 Allison Engine Company publication Engine design as related to airplane power : with particular reference to performance at varying altitudes which I have just posted at Engine design as related to airplane power : with particular reference to performance at varying alt

 

[GregP]

Very nice article, MiTasol. Thanks!

 

[swampyankee]

I believe that the government still owns the rights to IP paid for with tax money; the DoD can walk over to Pratt or GE and tell either to help the other build either F-22 or F-35 engines, as was done with the F101 engine the F-18.

 

[Zipper730]

But by 1940 most large aircraft engine manufacturers had test houses where they could control the atmosphere in terms of pressure/density and temperature to simulate high altitude flying.

While this might sound silly, did any have even basic test-cells prior to that?

It's just as a sort of time table to figure out what was do-able when...

The official start date for the R-4360 was in November 1940.

Thanks! It's nice to be able to have exact (or close to exact) numbers (other members will attest to this).

NACA's job was to advance the theory of flight not to apply it to practical everyday problems.

I suppose you're right, this is more an applied research area than a theoretical one.

There was something I was reading in an online PDF file which had to do with aircraft fuels and the methods by which aircraft and engine projects were managed in the US & UK.

One of the things that was mentioned was that certain decisions could be made by subordinates, and didn't have to be made from the top: Why wasn't that the case in the US?

 

[Zipper730]

I believe that the government still owns the rights to IP paid for with tax money

I remember, there was a big hubbub in the 1950's when the F-104 was being built and the USAF wanted to make it their default fighter and Lockheed fought it tooth and nail: It seemed to be an IP issue and frankly, I'm not sure I understand what the problem was: There were construction pools made during WWII and even Korea. I remember you'd see numerous cases of different manufacturers building aircraft (some B-47's were built by Douglas).

I was curious if that changed anything in the big scheme: I don't remember seeing these pools existing anymore by Vietnam or after.

 

[XBe02Drvr]

WWII was a total war national emergency and some of the practices of industrial competition were overridden by wartime needs. This mindset continued for awhile afterwards to a certain extent through the Korean conflict. By the time Vietnam rolled around it was competition as usual and as it was a "guns and butter" war, there was no overriding national emergency.
There still was quite a bit of spreading around of production, but it was in the form of contractors building subassemblies and the manufacturer doing final assembly. Building something as complex as an F4 entirely under one roof would require an impossibly huge and unwieldy plant.
Cheers
Wes

 

[swampyankee]

When I worked at Lycoming in the early 1980s, the Army threatened to pull AGT-1500 production. At that time, GE and Lycoming had a very bitter relationship, and GE had a bigger lobbying budget.

 

[Zipper730]

WWII was a total war national emergency and some of the practices of industrial competition were overridden by wartime needs.

Which continued through to Korea...

By the time Vietnam rolled around it was competition as usual and as it was a "guns and butter" war, there was no overriding national emergency.

The F-104 had nothing to do with this?

There still was quite a bit of spreading around of production, but it was in the form of contractors building subassemblies and the manufacturer doing final assembly.

It is weird that you don't have many contractors building one plane though... that seemed to have ended at some point in the 1950's...

When I worked at Lycoming in the early 1980s, the Army threatened to pull AGT-1500 production. At that time, GE and Lycoming had a very bitter relationship, and GE had a bigger lobbying budget.

So, GE won?

 

[swampyankee]

Which continued through to Korea...
The F-104 had nothing to do with this?
It is weird that you don't have many contractors building one plane though... that seemed to have ended at some point in the 1950's...

So, GE won?

In this case, no. I think the Army was using it more as a threat during contract negotiations.

 

[Shortround6]

I believe the M-16 rifle was one of the few modern weapons to be built in multiple factories (although the M-14 was also),
strange as politics and government contracts are the Government (army) wanted more than one source during the vietnam war, which is understandable.
However Colt had to turn over not only blueprints of the rifle but information on tools, jigs, manufacturing procedures/techniques and so on. The two other companies that built the M-16 at the time (everybody with lathe in the garage seems to be building them now) both charged more per rifle than Colt. One company charged almost double what Colt was getting per rifle in contract at the same time.
The strange part (and politics) comes in when at least one senator wanted to investigate Colt for excessive profits but not the other companies.