Spitfire MK XIV help

Failure of the tail retraction jack ram seals can also prevent the main gear being retracted and/or locking down as the fluid would cycle around the circuit and pressure would not build up.

This problem is identified by selecting the gear down before engine start. On start up the gear lever flicks into idle when pressure builds to 1100psi. If it does not click into “Idle”, you don’t go fly. This of course could also indicate failure of the hydraulic pump.

Initially the blow down bottle was connected to the main jacks only. A later modification added a shuttle valve to the tail retract jack so that all three legs could be blown down.

Technical answer

I doubt that this problem existed in wartime, unless there was a problem with supply of the rams.

The ram is double acting. It serves to raise and lower the tail leg, and also, by a bearing lock, locks the leg in the ‘up’ position when fully retracted. The doors are pulled up by the leg by means of an articulated link.

The rams are not easy to overhaul, and suffer from a number of design faults (which would not have been a problem in service). They attract moisture, which leads to corrosion of the shaft, and the seal housings, as well as the piston body. This leads to degrading of the seals, which fail in time, and lead to the problem of not being able to retract correctly, or more importantly, the jack being unable to overcome the downlock.

More recently, the problems have been largely overcome. The piston body can be separated from the two ends and remade. The end housing the seal pack can be chromed and ground, and the piston itself can be made from a better grade of steel. The seals are cotton impregnated, and whilst there was a poor quality batch doing the rounds, I think this has now been resolved by specialist companies.

I believe the initial problems may have occurred in Indian Air Force service – a lot of ex Indian airframes have the cutout for the leg to poke through, and later, the Rolls and BBMF aeroplanes were also so modified. Once the Spitfire rebuilding show got on the road, the problems were overcome, initially with surplus original parts, and later by completely (and expensively!) rebuilding them!

Bruce

Bombs on Spit XIVs

To (part) answer the other question – the only wartime use of bombs on Mk.XIVs that I have come across was limited use by 402 Squadron – and they carried a 500lbr on the centre-line not the wings. See ‘2nd Tactical Air Force Vol.3’ page 517.

Ouch!

Robs Lamplough’s stunning MkVIII, unless I’m mistaken?

There’s plenty of pics of Peter Teichman’s PL965 flying with her tailwheel locked down, too.

I have noticed that NH904 seems to have her tailwheel permanently locked down – or was this incorporated in the rebuild by Spencer Flack, in order to avoid the fate that seems to have befallen MV154 in that pic?

Spitfires with retracting tail wheels have proven troublesome in the past.

An intermediate mid term engineering fix for some has been to lock then in the down position and re-profile the the clam doors.

Mark

Thanks for the help, yes i did mean in WWII.

Good luck with Airfix Ollie, do mind those sticky fingers!!

Putting the thread back on track is that why the original Rolls Royce Spitfire RM689 had a fixed tail wheel?

Had always baffled me.

Ollie, if that was indeed the case, why didn’t you exclude that example from your request for information? In not doing so you stand the chance of wasting other peoples’ time looking for information you already have.

I thought i had made it clear.

Here’s a thought, Ollie Click here rather than cluttering up a thread because you’re too lazy to use Google.

Im not lazy, i am aware of TFC’s MkXIVe. I am looking for one with the camera positions on it. I have never noticed them on TFCs.

Google…. :rolleyes:

Although I think TFC’s Spit XIV is one? :confused:

I know this is not exactly on thread but is there a low back Fr14e around anywhere?
I ask due to having a model of a Mk14 on the bench at the moment.

How common would it be for a MK XIV spit to have the tail wheel locked down? and when done what happens to the gear doors?

You mean now or in WWII? These days it sometimes happens. If there is a problem with the retract mechanism and there is no time or parts to make an immediate repair you can disable the retract system and fly with the tail gear locked down. In these cases the usual treatment of the doors is to have them locked closed with a semi-circular cut-out in each door to fit tightly round the leg. If you look carefully at an old pair of doors you will often see these cut-outs filled in with a rivetted repair patch.