Fi 103 - the other V weapon

Spent some happy hours working on the 3 view to sharpen up the lines for the tile printed plan.

It is quite long!

Looks like there's going to be a huge downward pitching moment!

Downward pitch? Surely no worse than in the full size - ah - but that never tried to glide.

It is interesting to note that the engine cut out before it hit the ground was not intended but simply a result if the fuel feed to the pulse jet was unable to handle the negative g as the elevator was put full down.
It was not clear if or when the Germans knew it was happening but it certainly added to the terror effect.

I thought they ran until the fuel was exhausted, which is why most of them flick-rolled as the jet died, the autopilot was trying to hold the altitude and heading, until the little wing stalled.

Its range was controlled by counting the revs of the little prop on the front. The prop also armed the warhead after a certain number of revs to protect the launching site.
Fuel consumption was rather erratic and could not be accurately checked beforehand as the pulse jet shutters only had a very limited life before its vanes started to fatigue and fracture.

The Ford spent some effort trying to improve the shutter life on the American version (JB-2 Loon) in an attempt to increase its range but only extended the average life by a few minutes regardless of the material used.

With adequate thrust having been demonstrated work can start on the fuselage.
On the Natter I used 'ring' formers cut out of 3mm Depron. It worked well enough but the formers are relatively weak so the fuselage can be fairly easily crushed by a point load, typically your fingers holding it for launch or a tuft of grass during a belly landing. Solid formers would better resist crushing but would contain 3 or 4 times the material.

On the V1 fuselage the ring formers are thinner (2mm Depron) but the inner edge is reinforced with a 9mm wide flange. In conjunction with the skin each former becomes a circular 'I' beam.

The 6 formers of the 13" centre section.

The disks cut out of the centres are large enough to be used as some of the nose and tail section formers.

Just had to see if it could actually be put together.
The first two planks go on.

Built like this it will a miracle if it does not end up a banana but so far so good! :woohoo:

Just make a tube from thin card and then it will be straight.

Banana shape is same as a boomarang- least it will come back! :silly: Whats the diameter measurement across the inside the circle?

Use a plumb-bob down the centre of the rings, to a centre mark on the paper at the bottom.

The centre section complete.
From the inside it looks more a bit of the hull of a nuclear submarine. :ohmy:

The next sections will have much more taper so the fuselage will be made up of 4 pieces as well as a solid nose and tail cone.
In this way the required taper of each plank is reduced so reducing the cutting waste.

The centre and two tail sections.

The wings go in the centre section.
The tail plane and fin go in the last tail section, but I have no idea yet how they will be fitted. :huh:

Then the two tail sections will have to be joined to fit pulse jet.

Then...........I cant think that far ahead! :woohoo:

You are so neat!!! That looks cool, gonna look good next to your new TX hehe

Time to start thinking about the tailplane as it has to be fitted and be fully operational before any of the fuselage sections can be joined.
The lower 2mm Depron skin and the 'spindled' hard balsa spar.

The complete tailplane with elevators in position.

The elevators have a fully shrouded hinge line.

Operated by a single 5g servo in the fuselage tail section.

Testing the tailplane and elevator mounted on the fuselage tail section.

The servo and linkage will be completely built in.

The elevator has 4 'bearings'. Two on the glass fibre tube joining the elevator haves and 'pin' hinges out board.