FP_2015_05_

FROM THE WORKSHOP MOSQUITO PROTOTYPE

when, fitted with Merlin 70 series

engines, it was not only the fastest

Mosquito ever to fly but also the

quickest aircraft in the world.

The first task was to remove the

original fabric. It was a shame to

have to lose it but essential to get

down to the underlying wooden

structure for careful inspection.

Fortunately, damage was less

than was feared: the main issue

was Bulkhead 2, at the rear of

the cockpit, which had become

detached from the fuselage

skin and needed re-gluing and

screwing into position.

There was dry rot around the

cockpit door, which was treated

and a new piece of ply skin scarfed

into place. Several areas suffering

from ‘hangar rash’ were repaired

using filler made from fine Sitka

spruce sawdust and glue.

The wing had fared much better

than we expected. The main areas

of concern were on the trailing edge

just inboard of the wingtips. Poor

drainage had led to rot in the wooden

structure. Where possible the original

wood was treated; however, a couple

of small ribs had to be replaced and

a new ply skin was also fitted. There

had also been water ingress around

one of the starboard filler caps which

also needed treatment and a new

piece of ply skin.

Unique prototype features

Originally fi tted with Rolls-Royce Merlin 21s, the exhaust system was internally

ducted within the cowlings with a single exhaust low down on each side.

Engine nacelles were shorter than the later production models, allowing for a

single-piece fl ap which spanned both sides of the nacelle.

The tailplane had a span of 19ft 5½in – increased to 20ft 9in on production

aircraft.

The ailerons and the elevators were initially metal-framed and fabric-covered.

They were later superseded by all-metal versions.

The prototype was the only Mosquito to be fi tted with Handley Page leading

edge slats.

It was the only Mosquito to feature a wing span of 52ft 5in. On production

aircraft it was increased to 54ft 2in.

The prototype, marked as E0234, being

prepared for ground runs at Hatfi eld. Note the

internally ducted exhausts. BAE SYSTEMS

114 FLYPAST May 2015

The leading edge slats on W4050, long since

hidden.

Bulkhead 2, just behind the cockpit,

needed repair.

112-116_Mossie_fpSBB.indd 114 16/03/2015 14:33