Hampden help wanted.

[Mr.Creak]

I recently had the (possibly mad) idea of Hampden re-done in the style of the A-26 Counter Invader, tip tanks, underwing weapons etc¹ to cover ground forces in my Latin-American wargames campaign (don't ask, it's based around independence for a former British colony/ protectorate).
What I can't work out is that the A-26 was considerably faster (355 vs. 247 mph) with twice as much power (2 x 2,000 hp vs. 2 x 1,000 hp) but still managed to weigh ~60% more (15,900 kg² vs. 10,206 kg [all figures Wiki]).
I know that the power would available, using the Centaurus, but were the aerodynamics of the Invader that much better?
Admitted the extra wing area on the Hampden may have had an effect, as, possibly, would the extra length since they both contribute to wetted area and thus, so far as I know, drag.
Anyone any ideas?

1 And, very probably, a solid nose with a Molins. Or pair of bofors 40 mm.
2 Yes I know, I switched from Imperial to metric units.

[maxmwill]

I think that the A26 had a more robust structure, as opposed to the Hampden, which might account for the greater speed.

Judging from a three-view, the Hamp does appear to be more delicate.

[Mr.Creak]

Ah, thanks.
"Structure" is much more easily whiffed!

[KJ_Lesnick]

Mr.Creak

Aerodynamics: The A-26 used a NACA 6-series airfoil which could be lower drag at higher speeds

Structural: The A-26 was quite sturdy and at some weights (bombs off probably) and altitudes could turn inside an Me-109 (this was in a documentary, and in the documentary was none other than LTC Paul "Max" Moga, and he seemed surprised as well).  A-26's sometimes got into dogfights with fighters, and sometimes they flew out alive.

[wuzak]

The Bf 109 wasn't a fantastic turner to start with, but I still doubt the claim.

You said "at altitudes", but the A-26 had a relatively low service and absolute ceiling.

[KJ_Lesnick]

Wuzak

I said at some weights and altitudes... those weights might have been after the bombs came off, and somewhere between 0 and 22,000 feet

[jcf]

FWIW you'd be better off with a pair of the higher power later series Hercules than the Centaurus,
as the weight and power of the latter would seriously overstress the Hampden design.

And yes, the aerodynamics of the Invader were that much better, which isn't surprising as it was
circa 1940-41 state-of-the-art whereas the genesis of the Hampden was in the early 1930s.

[Army of One]

Ha......!! I liberated the Hampden kit out of my sons Airfix VC boxing last year.......with exactly this sort of idea......i also considered a beefier version for a sub basher.......solid nose, guns, rp's.....more guns.......my main stumbling point was the engines......what to beef it up with.......i wanted radials for reliability and durability..........and some sort of beefed up (bigger gun.....maybe a .50 or two) rear upper turret.......I'll be watching this with great interest........

[jcf]

Lot's of stuff in the Hampden/Hereford Thread:
http://www.whatifmodelers.com/index.php/topic,24619.0/highlight,handley+page.html

The M.15/35 was a proposal for a widened fuselage version fo the Hampden with Merlin XX or Hercules, pic at the linked comment:
http://www.whatifmodelers.com/index.php/topic,24619.msg359713.html#msg359713

[Captain Canada]

Sounds interesting. Don`t see many Hampden whiffs about and the mods you plan will really give her an updated look. And as you say, structure is easily whiffed