Reggiane RE-2007 - What if?

[delcyros]

That´s it, Lanc. With increasing drag you loose speed (and range). I believe that the Re-2007 would need a new fuselage design (since the Jumo-004 doesn´t fit) or beeing replaced by BMW-003 A2 (with less weight and less sustainable thrust) powerplants. Both would need considerable time (and thus also delaying the development of the Re-2007, so a timeframe between mid 45/late 45 and early 46 for ti´s deployment would be possible).
The given range is overrated a lot, the Re-2007 would more probably have a comparable range with the He-162 than anything else (at best).
The speed is also overrated. The drag produced by the canopy and (thick?) wings would be quite large, even with slightly swept back wings. I really don´t see why it should have a comparable speed to the soviet MiG-15 / La-150 (which also are small and light weighted planes) while it lacks so much thrust?! A speed between 520 and 570 mp/h is more probable than a speed between 600 and 650 mp/h.

 

[the lancaster kicks ass]

yeah i mean that's a huge speed for a plane like that........

 

[cheddar cheese]

oh god if CC reads this he's gonna claim that the designers of the F-86 copied the italains an he'll try and use the fact that the F-86 was so goo dto claim the RE-2007 would have been amazing and i'll get really annoyed.........

thans for pointing that out guys........

You read me like a book

 

[the lancaster kicks ass]

i know you too well.........

 

[red admiral]

The Speed figure might not be as far off as you think. If you look at the other Italian fighters, G.55 et al, they were doing 400+mph on only 1500hp. There were other designs, e.g. the SAI 207/403 that could do 400mph on only 750hp. This would leave me to believe that the Italians have very clean airframes.

 

[the lancaster kicks ass]

yes but think how much heavier this jet would be...........

 

[cheddar cheese]

Weight shouldnt really have much to do with top speed. Just look at the P-47, for example.

 

[the lancaster kicks ass]

yes but the P-47 also had a hugely powerfull engine...........

and as a car man you should know that weight has allot to do with speed...........

 

[cheddar cheese]

No, as a car man I know that weight kills acceleration and handling. Top Speed is largely unaffected.

 

[the lancaster kicks ass]

ok well take into account pewer to weight ratios..........

 

[cheddar cheese]

Again, more to do with acceleration and handling 8)

 

[delcyros]

Bring it back to aerodynamic drag. The calculation looks quite similar to the early Messerschmitd speed estimations of the Me-P.1101, which wered in general about 50 mp/h higher. A correct mathmatical solution for high subsonic and transsonic speeds (including compressability effects) wasn´t found earlier than january 1945 (by means of DFS). And again: thicker wings increase the drag, so you have to choose: either greatly reduce the range or reduce speed and range moderatly. This leaves the Re-2007 in a difficult situation. As would the needed redesign of the fuselage because of the larger Jumo-004 B engines. Larger fuselage diameter also increase the drag and weight. At least the low thrust of a single Jumo-004 B makes any speed over 600 mp/h very questionable. Extremely clean lines and thin, swept back wings would be needed, the area rule and a very small airframe would be necessary, too. I cannot see these details in the Re-2007 design...

 

[the lancaster kicks ass]

nor can i...........

 

[cheddar cheese]

The drawing on the first page depicts swept-back wings.

 

[red admiral]

The problem is that most of the pictures are artist's impressions not technical drawings. Now if we had technical drawings, then we could maybe get somewhere. The Caproni-Campini also has thin wings, but huge range.

 

[the lancaster kicks ass]

ok i can't actually find the "Caproni-Campini", what's it's proper designation? but if it's like the rest of the Caproni familyit'll have big fuel tanks and more engines, each engine having better fuel economy, do you realise we're simply sayin it'd have thin wings if it's gonna go fast, but thin wings also mean that less fuel can be carried as none can be carried in the wings and they produce less lift than a thicker wing, however if it's gonna get more range the wings'll have to get thicker to produce more lift, incresing drag and slowing her down...................

 

[cheddar cheese]

Go to the first page of "Best Jet of WW2" that bronze created in the polls section and look at the bottom. I tried pasting it but my interent spazzes every time I try.

 

[the lancaster kicks ass]

wow, an un-armed plane doing 375kmph, now i'm scared

 

[delcyros]

...it is true that we don´t have any construction charts, but there is a possibility to determine how probable a speed of 650 mp/h is as long as the design is driven by a single Jumo-004 B.
Jumo-004 B: weight: 742 kg (~1600 lbs), thrust: 890 kp (1958 lbs)
Let´s say we have a very clean airframe and a featherweighted design (comparable to a He-162). The increasing drag at speeds close to Mach 1 would force the designers to greatly increase the engine thrust (at a drag factor of 0.9):
550 mp/h ~ 2000 lbs thrust
600 mp/h ~ 3500 lbs
650 mp/h ~ 6000 lbs
this is a roughly estimation but it can be verified:
Ar-234 C with four BMW-003 allowed a top speed of 562 mp/h (~drag factor of around 2,6)
Me-262 a with two Jumo-004 B allowed a top speed of
max. 540 mp/h (~drag factor 1.8 )
P-80 would allow a top speed of 577 mp/h with roughly 4000 lbs thust (~drag factor 1.3)
The Ho-IX V2 (twin engined jet) flying wing (LOW DRAG!) design allowed a top speed of 607 mp/h (drag factor ~ 1.0) Ta-183 (hypothetical) with a single He-S011 B (1300 kp or 2860 lbs) would allow around 597 mp/h. This indicates a drag factor of around 0.88
Which drag factor allows the Re-2007 with 2000 lbs thust to reach 650 mp/h in level flight? Can tell you: 0.26 !!! Impossible.
This would rather indicate a few stabilizers around a single Jumo-004 B (and even this is questionable) and surely no plane. Even the F-86 and Mig-15 hardly match a drag factor of around 0.75-0.8!
For 600 mp/h, a drag factor of around 0.5 would be necessary (still highly unprobable, maybe a single engined flying wing design?).
For 550 mp/h a drag factor of around 0.9 (which still is very good) would be necessacy. This is possible, but questionable (not to count compressability effects).

 

[Civettone]

I'm terribly sorry but the Re.2007 is a myth. A post-war development by Reggiane to allow his company to stay in business.

Kudos to the many members who immediately became suspicious of the Italian design and especially the overrated performance stats.

Information comes from the rather well known Max Cappone. Take a look at this website: http://cloud.prohosting.com/hud607/uncommon/aircraft/re2005/re2007.html

Kris