109 e3b against spitfire II

[Crumpp]

Check the math on that document....

1430lbs / 1175hp = 1.21 lb/hp not 1.13lb/hp....

The Merlin has the same power to weight at the DB601.

[Seadog]

Originally Posted by Crumpp

Check the math on that document....

1430lbs / 1175hp = 1.21 lb/hp not 1.13lb/hp....

The Merlin has the same power to weight at the DB601.

It actually states 1450 lbs but also 1240hp at 2850rpm @ 10,000ft (two values given for the Merlin XX)

However, the DB601N power is WEP. The equivalent figure for a Merlin XX would be 1485hp at 14lb/3000rpm @ 6000ft and 1490hp at 16lb/3000rpm @ 12500 ft and 1280hp at 3000rpm/12lb @ TO, at least in 1942 but the TO figure is applicable to 1940 as well.

[robtek]

you actually implement that in a comparision wep is set against full mil.????
You are talking about the N, not the A.

[Crumpp]

Merlin XX would be 1485hp at 14lb/3000rpm @ 6000ft and 1490hp at 16lb/3000rpm @ 12500 ft and 1280hp at 3000rpm/12lb @ TO

The document compares the operational engines at the time it was prepared. At 17500 feet, the document is correct in the power output of a Merlin XX at it's approved Emergency Power rating of +9lbs at the time the engine were compared. It is also correct in its assessment of the DB601N series.

It is not correct in its math of the power to weight ratio of the engines. The Merlin XX is the same as the DB601N.

You need to look at the DB605 series to compare those other ratings. Also ensure you are looking at the correct power, ie...indicated, static or RAM, Brake or Thrust, and if it takes into account exhaust thrust...

[Seadog]

Originally Posted by Crumpp

The document compares the operational engines at the time it was prepared. At 17500 feet, the document is correct in the power output of a Merlin XX at it's approved Emergency Power rating of +9lbs at the time the engine were compared. It is also correct in its assessment of the DB601N series.

It is not correct in its math of the power to weight ratio of the engines. The Merlin XX is the same as the DB601N.

In Nov 1940 the operational limits of the Merlin XX were 12lb/3000rpm TO = 1280hp, and 12lb/3000rpm @8500ft = ~1360hp in MS gear. Operation of the boost cutout would give ~14lb in FS gear, but I don't know exactly when official approval was given, however this capability was present in all Merlin XX engines.

At 1280hp and 1450lb weight gives lbs/hp = 1.13 but I agree that the values given in the chart were confusing.

[TomcatViP]

So I understand now what's all abt lol; You hve been so scared abt the dynamic capacities of the Spit ? The guys that did mod the FM in IL2 did used badly wrong assumptions.

Stay at high speed . Don't over G. Don't put yourself where you'll need AoA and I swear you'll knock down any 109 even at full mil power. Big wings are made for that !

Damn Seadog Is that really a "Cat" tht hve to ensure you on this point ?!!