Author Topic: Some Mosquito durability, fuel burn and misc data (Read 1347 times)

Scherf · « **Reply #15 on:** March 17, 2004, 10:11:21 PM »

The HX802 curve above looks very much like a Mossie VI with Merlin 25s and 150-octane fuel (see other thread HoHun refers to).

I have no way of demonstrating / proving this however. Neil Stirling's your man on that one. I've based my "guess" on documents he posted over at Butch 2k's late & much-lamented WWIIAW board.

Cheers,

Scherf

HoHun · « **Reply #16 on:** March 18, 2004, 01:07:15 PM »

Hi Karnak,

>Can you explain the how M.S. gear and F.S. gear worked on HX802 in the above chart?

The gears worked in the standard way for a 2-speed supercharger. The curve looks simply unusual because very high boosts were used so that the M.S. (low) gear has a full throttle height of sea level (or less).

You'd not normally design an engine that way, it's the result of extending an existing engine's envelope.

>Is M.S. gear something that the Merlin 25 normally lacked?

No, it was a component of the standard Merlin 25. It shows in the Mk. 6 speed curve as well with a full throttle height of 5500 ft. (The higher altitude results from the lower boost used for these curves).

>How would that appy to a Mosquito powered by Merlin 25s with manifold exhausts?

The manifold exhaust create additional backpressure and kill part of the exhaust thrust, so they slow down the aircraft.

As a result of the previous discussion, I tried to match all of the Mosquito data I could find, but it seems contradictory.

Shooting from the hip, I'd say 360 mph @ sea level should be within reach for a Merlin 25/+25 lbs/sqin boost Mosquito VI with ejector exhausts.

Regards,

Henning (HoHun)

Karnak · « **Reply #17 on:** March 18, 2004, 03:04:13 PM »

HoHun,

What speed would you guess for a Mosquito Mk VI, Merlin 25, ejector exhausts, +18lbs boost at sea level?

HoHun · « **Reply #18 on:** March 18, 2004, 04:58:24 PM »

Hi Karnak,

>What speed would you guess for a Mosquito Mk VI, Merlin 25, ejector exhausts, +18lbs boost at sea level?

HJ809 got 332 mph with saxophone ducts and external tanks at +18 lbs/sqin/3000 rpm at sea level.

The Mk 6 in the above graph gets 337 mph, everything equal except that it carries no external tanks.

Assuming the Mk 33 in the above graph is identical to a Mk 6 in every regard except the ejector exhaust, that would give us a 344 mph sea level speed for the Mk 6, too.

The report on HJ809, on the other hand, mentions that B. IV DK290 gained 13 to 15 mph from ejector exhausts at just +9 lbs/sqin, so maybe the FB VI speed might even be 352 mph.

(I'm not sure whether the 5 mph loss for the addition of external tanks is realistic, though. A different value here would change the end result, of course.)

Regards,

Henning (HoHun)

Karnak · « **Reply #19 on:** March 18, 2004, 05:44:25 PM »

HoHun,

Thanks for the reply.

I have used the 10-15mph gain to guess it at 348-353mph based on the 338mph that HTC uses.

I really, really wish our Mosquito VI had ejector exhaust instead of manifold.

thrila · « **Reply #20 on:** March 18, 2004, 06:37:28 PM »

dunno if you guys have seen these before...

mossie notes

AFAIK the flaming mossie got fixed a while back. I don't get set on fire half as much as i used to.

I quite like flying the mossie as a pure fighter, it's not bad at all. It does bleed E bad but that can be used to your advantage. Nothing like making someone blow right by you and lighting him up with 4 20mm.

However it also accelerates poorly in level flight (the only real thing i dislike about it), however it does accelerates great in a dive.

I sure wouldn't mind an extra 10-15mph though.

I do love the mossie.

Edit: just notcied this look at a) does this means mossies could carry dt's + rockets?

Karnak · « **Reply #21 on:** March 18, 2004, 06:48:37 PM »

thrila,

Yes, I usually use it in pure fighter mode as well. It is a lot more responsive than people usually give it. Only thing about diving is that if you don't watch your speed you're liable to lose major control surfaces when you try to pull up. I've managed to lose all control surfaces once, usually it is both elevators or both ailerons though.

I still catch on fire constantly though. I haven't noticed a change there.

I have the Mossie 6's handbook in PDF format.

EDIT:

Yes, in 1945 they equipped Mossie 6's with a two layer rocket launch system next to the drop tank. It was still four rockets under each wing.

thrila · « **Reply #22 on:** March 18, 2004, 07:16:39 PM »

i have to agree, the diving is a bit of a bugger. It dives so well but is handicapped by the fact it falls apart easily if you get too fast. I'm not sure if the top speed of which it falls apart is lower than most planes (it sure feels like it tho) or if it's just an illusion because it dives so darn well. I've lost control surfaces on many occasions when diving a con:( If i don't watch the speed and the cockpit begins to shake i daren't touch the stick. I throttle back and veeery slowly trim up.

I've shotdown some notable people when flying the mossie, i believe the fact that the mossie is under rated by many contributes significantly to my kills in it.

So they did have dt's + rockets, that's great.

Wish we had that loadout in AH, it would be nice for long range raids. That could actually give the mossie a nice role in AH over other fighterbombers. Hopefully the fuel consumption issues will be looked at for AHII.