Author Topic: Reggiane 2005: La-7 killer (Read 379 times)

Widewing · « **Reply #15 on:** November 22, 2002, 01:05:04 AM »

Quote

Originally posted by Gryffin
I must be misreading the chart or something ... it seems from the blue and green lines that from 13,000 feet altitute to 20,000 feet altitude, this thing is actually slower with emergency power than with military power ... widewing?

Whoops! you're right! I connected the wrong dots! I have uploaded a corrected chart.

I have read where two supercharger designs were tested, one for high alt, and a second one optimized for low altitude. I have seen reference data to the Alfa Romeo built DB-605A with MW-50 as producing 1750 hp, not quite as good as the DB-605D that made 1875 hp, but not far behind. According to one source, Italian 605s consistantly made better power than the German built equal. It seems that Alfa Romeo held tolerances much tighter. The down side was that it took much longer to produce engines. This, added to the Allied bombing, resulted in a constant shortage of engines.

Irrespective of low level speed, the fact that the Re.2005 was 30 mph faster than the Macchi 205 and Fiat G55 using the same engine is significant. Gregor's wing design (he was Seversky's aerodynamic wizard) was among the lowest drag producing wings of its time. Its chord to thickness ratio was similar to the Spitfire's. I recall that this design had a critical Mach of .80, better than the Bf 109 or FW 190.

My regards,

Widewing

GRUNHERZ · « **Reply #16 on:** November 22, 2002, 01:08:43 AM »

No way this plane hits 425 mph at 7k, thats not that much slower than a P51H....

GRUNHERZ · « **Reply #17 on:** November 22, 2002, 01:17:16 AM »

6,560 ft / 2,000 m: 421 mph / 678 kph
13,120 ft / 4,000 m: 351 mph / 565 kph
22,800 ft / 6,950 m: 421 mph / 678 kph
22,965 ft / 7,000 m: 421 mph / 678 kph

Widewing these numbers you used make no sense, why the 70mph drop from 7K to 13K? Why are speeds identical at all other altitudes?

Do you have any support for these numbers other than that website?

Vermillion · « **Reply #18 on:** November 22, 2002, 06:19:16 AM »

Those numbers are much higher than any I've ever seen for that plane.

gatt · « **Reply #19 on:** November 22, 2002, 06:21:41 AM »

Widewing, stop this nonsense pls

The Re2005 has never been faster than the C.205V. Actually, the G.55 and the Re2005 were as fast as an early 109G-6, but performed better than the C.205V above 18-20K thanks to their lower wing load.

The DB605 that Series 5 fighters (Re.2005, G.55 and C.205V) mounted was an early A1 model, with 1.475hp at 1.4ATA. Moreover, Italian pilots were forbidden to push their engines at more than 1.3ATA.

Your 1.750hp DB is actually the DB603. No DB603 engined Re.2005 (re-named Re.2006) has ever been built. It never left the drawing board. Only two DB603 engined G.55 (re-named G.56) have been built and tested. The G.56 was actually an oustanding fighter: about 440mph TAS at 23K, armed with 3x20mm and 2x12,7mm .... a nice perk plane indeed.

Widewing · « **Reply #20 on:** November 22, 2002, 08:24:04 AM »

Quote

Originally posted by gatt
Widewing, stop this nonsense pls

The Re2005 has never been faster than the C.205V. Actually, the G.55 and the Re2005 were as fast as an early 109G-6, but performed better than the C.205V above 18-20K thanks to their lower wing load.

The DB605 that Series 5 fighters (Re.2005, G.55 and C.205V) mounted was an early A1 model, with 1.475hp at 1.4ATA. Moreover, Italian pilots were forbidden to push their engines at more than 1.3ATA.

Your 1.750hp DB is actually the DB603. No DB603 engined Re.2005 (re-named Re.2006) has ever been built. It never left the drawing board. Only two DB603 engined G.55 (re-named G.56) have been built and tested. The G.56 was actually an oustanding fighter: about 440mph TAS at 23K, armed with 3x20mm and 2x12,7mm .... a nice perk plane indeed.

Ok gents, a quick check with Max Cappone’s data provides accurate numbers on the Re.2005. Max is easily the foremost expert on Reggiane aircraft.

Taken from actual Regia Aeronautica acceptance tests, speeds are as follows:

Sea level: 334 mph
2000 M: 348 mph
4000 M: 373.5 mph
6500 M: 394 mph
7000 M: 401 mph
8000 M: 388.5 mph

Note: This aircraft did not have loaded guns and fuel state is apparently not recorded.

421 mph was indeed obtained, but only by over-boosting the engine. Unfortunately, almost all sources refer to the 421 mph speed as typical. Angelucci and Green both refer to this number.

I have an e-mail into Max for additional info.

By the way, two 2006 airframes were built, with one completed but not flown due to the Italian surrender.

My regards,

Widewing

Turbot · « **Reply #21 on:** November 22, 2002, 09:34:58 AM »

bah! The 109f4, F4U, about all of the 190's plenty of planes more than able to do in La7's. It's not the fault of the plane.

But more planes are better, everyone likes to have more planes.

GRUNHERZ · « **Reply #22 on:** November 22, 2002, 09:52:26 AM »

Yep those numbers make more sense, but the G55 is still prettier!

DoctorYO · « **Reply #23 on:** November 22, 2002, 01:26:59 PM »

Just What we need another cheese mobile..............

Plenty of late war monsters already lay off the freebase...

Regards,

DoctorYO