@tomo pauk Do you have any more details on that 2-stage turbo-supercharger design? It sounds like a good way of eliminating the power sapping engine driven second supercharger.
IMO that was certainly a good idea. Both impellers were of the 'mixed flow' variety, with wide chord blades, the air entering the impeller axialy (ie. paralel to the impeller axis) and compressed air leaving at approx 45 deg into the collector. Second stage also fed the air to the hollow blades of the turbine, thus making possible attaching it next to the engine with it's hot exhaust gasses not representing the problem.
Continental and Chrysler engines, along with the Lycoming, Wright, Pratt & Whitney et al, failed. The Ford engine didn't fail. As an aero engine, it was not called upon and developed, but as a tank engine in V8 and V12 configurations, it was largely successful, and remains a highly tuned tractor-pull engine today. The added complexity and tighter tolerances remark may require explanation. Merlins made at the Trafford Park facility were made to revised tolerances for what Ford deemed to be proper mass production, as they were at Packard, and Ford's Merlins were noted for reliability. Improvements to the valve gear and con-rods may seem complex, but were just modern improvements accepted as quite normal today. The turbo and fuel injection systems remain of conjectural nature, and you can think any way you want one way or the other, without validation of any sort, but the Bosch fuel injection system to be used did function in German engines.In any case, the Ford engine seems promising if it could actually achieve the projected performance reliably. The same could be said of the Continental and Chrysler engines of the era though and neither of those ever quite got "up-to-snuff" during the war so I am in doubt of Ford's ability to get theirs running any better. The overall design seems a great improvement but the added complexity and tighter tolerances--while improving performance--may have a detrimental impact on the serviceability of the engine in the real world.
Apologies for digressing on behalf of other readers, but I think a lot of confusion is caused by tolerances vs clearances. As I understand it the first is how much the dimensions are allowed to vary before they fail quality control, the second is how much of a gap there is between the parts.revised tolerances for what Ford deemed to be proper mass production, as they were at Packard
I doubt their ability to just turn up with their own first-attempt engine and do better than the competition.
It's totally understandable to doubt. I've doubted the viability of Ford engines in the past. It's also fact that they built, on production tooling, and engine that worked, in a short time, and developed successful tank engines based on the design, which doesn't mean a top-notch aero engine would result, but doesn't at all mean that it wouldn't, and I believe it was a tremendous opportunity missed.
Apologies for digressing on behalf of other readers, but I think a lot of confusion is caused by tolerances vs clearances. As I understand it the first is how much the dimensions are allowed to vary before they fail quality control, the second is how much of a gap there is between the parts.
Ford certainly made good aero engines with the help of established aero-engine firms, but I doubt their ability to just turn up with their own first-attempt engine and do better than the competition. It's not like BMW/DB/RR/CW/P&W/Allison etc etc found this stuff a walk in the park.
Hard to tell if it really was an opportunity. The R-3350 was also built on production tooling, it worked, and in a short time. It didn't turn into a tank engine, but it did turn into a top-notch aero engine. However it was also a bitch to get the bugs out of. Coincidentally the R-2800 also first ran in 1937, I believe P&W had it on tooling pretty fast, it was very good, not a huge amount of problems.It's also fact that they built, on production tooling, an engine that worked, in a short time, and developed successful tank engines based on the design, which doesn't mean a top-notch aero engine would result, but doesn't at all mean that it wouldn't, and I believe it was a tremendous opportunity missed.
Coincidentally the R-2800 also first ran in 1937, I believe P&W had it on tooling pretty fast, it was very good, not a huge amount of problems.
Dodge ended up supplying many of the fixes that ended up making their production in Chicago far more reliable than the C-W production.C-W's lack of responsiveness to AF requests for solution to R-3450 failures, resulted in their virtual exclusion from future military procurement (except for low quantity civilian variant turbo compound and trainer engines and a licensed British designed turbojet- no aircraft.) I was in the USAF sufficiently long ago to have gotten much of my opinion of C-W first hand from some of their victims.
I like that, but would like to see how the landing gear would sort out
Never figured out why they didn't switch to steel, like they did with the R-2600 Twin CycloneLots of magnesium there to fuel a mainspar burnthrough, if the aircraft had not yet rolled inverted into the Pacific off the end of the runway.