Vampire FB6 (ejection seat equipped) cockpit changes?

[wellsprop]

Hi all,

 

I'm converting Airfix's Vampire F3 into an FB6, upon replacing the kit seat with an ejection seat, I've realised the ejection seat must have been placed significantly further aft, to keep the pilot in the same position.

 

 

The above photo appears to show that the fuselage, immediately rear of where a non-ejection seat would go, has been removed and the ejection seat occupies that space. Is this correct, has anyone got some cose up/in cockpit photos of an ejection seat equipped Vampire (such as the one at the De Havilland Hatfield museum)?

 

Cheers

Ben

[wellsprop]

I've mainly resolved my own question, the image here nicely shows that the ejection seat headrest remains in the same place as the non ejection seat headrest, but the ejection seat sits further aft in the cockpit. How the internal cockpit arrangement looks, I am not sure.

 

https://www.airplane-pictures.net/photo/1349604/hb-rvn-private-de-havilland-dh-100-vampire-fb-6/

 

I assume the bulkhead either has a cut out, or is moved entirely further aft.

[canberra kid]

If the Venom pod is the same as the late Vampire then this may help? The seat rail would be mounted on bulkhead 2 in the attached drawing.

  

John

[bigbadbadge]

Sorry to piggy back on this, but would that be the same for the FB.31?  I have the MB  Mk.2 Ejector seat already and just planning ahead for when I start, building it.

Thanks in advance and again sorry for the thread Hijack. 

Chris

[wellsprop]

On 12/10/2022 at 19:51, canberra kid said:

If the Venom pod is the same as the late Vampire then this may help? The seat rail would be mounted on bulkhead 2 in the attached drawing.

  

John

 

I would be surprised if the Venom were significantly different from the Vampire. From the drawings I have, bulkhead number 2 is shown as being in roughly the same position (or at least, the same relative position).

 

The problem I have, is it is very evident from the pictures in the below link, that the back of the ejection seat is hard up against the back of the canopy. This leads me to believe the seat must have been moved further aft. 

 

 https://www.net-maquettes.com/pictures/de-havilland-vampire-walk/

 

Comparing the dimensions of the non-ejection seat and the Martin Baker Mk 2FV, the ejection seat would position the pilot, much, much further forward than the normal seat, if the seat rails were up against bulkhead 2. This is all just guess work and approximation on my behalf. 

 

23 hours ago, bigbadbadge said:

Sorry to piggy back on this, but would that be the same for the FB.31?  I have the MB  Mk.2 Ejector seat already and just planning ahead for when I start, building it.

Thanks in advance and again sorry for the thread Hijack. 

Chris

 

I would guess it would be the same. No worries the FB31 is as applicable to my question as the FB6. 

[wellsprop]

On 12/10/2022 at 19:51, canberra kid said:

If the Venom pod is the same as the late Vampire then this may help? The seat rail would be mounted on bulkhead 2 in the attached drawing.

  

John

 

I would suggest that this image shows that the ejection seat sits further aft than bulkhead 2. Even accounting for parallax error, the rear of the ejection seat is aft of noticeable panel line where bulkhead 2 is. 

 

http://milky01.co.uk/wp-content/uploads/2018/12/182.jpg

 

 

It looks as if the headrest sits a couple inches forwards of the plane of bulkhead 2, this is as I would expect, i.e. The pilots head doesn't not change position between the  ejection and non-ejection seats in the Vampire. 

[bigbadbadge]

Thanks Ben and that is a cracking image Ben it certainly helps,  from that and the angle of the back of the seat I will be able to place it. 

 

Chris

 

[wellsprop]

44 minutes ago, bigbadbadge said:

Thanks Ben and that is a cracking image Ben it certainly helps,  from that and the angle of the back of the seat I will be able to place it. 

 

Chris

 

 

I'm currently working on a conversion for the FB6 and FB31. 

 

Using various plans and images, I've modelled the ejection seat. To match up the position of the ejection seat, with the images and plans, I've had to extend the bulkhead rearwards by 4mm.

 

 

Im not quite sure how this compares with the real cockpit bulkhead, but it's the only way I can match the position of the ejection seat relative to the plans and images.

 

The Airfix seat (non ejection) has a back thickness of about 1.2mm at the top of the seat, with a taper of about 10 degrees between fore and aft faces of the seatback. The ejection seat has a thickness, from front cushion to rear rail, of approximately 4mm. The thickness of the headrest is approximately 5.5mm.

 

A quick bit of maths, to ensure the same relative head position, subtract the thickness of the Airfix seat from the thickness of the ejection seat headrest, approximately 4mm.

 

Either I'm roughly correct, and the seat was indeed moved aft of the angled bulkhead, or I'm completely missing something.

 

What I'd like to do is get in the cockpit of an ejection seat equipped vampire, with a tape measure and work our relative positions (or see for myself if there is a cut out in that bulkhead). 

[bigbadbadge]

1 hour ago, wellsprop said:

 

I'm currently working on a conversion for the FB6 and FB31. 

 

Using various plans and images, I've modelled the ejection seat. To match up the position of the ejection seat, with the images and plans, I've had to extend the bulkhead rearwards by 4mm.

 

 

Im not quite sure how this compares with the real cockpit bulkhead, but it's the only way I can match the position of the ejection seat relative to the plans and images.

 

The Airfix seat (non ejection) has a back thickness of about 1.2mm at the top of the seat, with a taper of about 10 degrees between fore and aft faces of the seatback. The ejection seat has a thickness, from front cushion to rear rail, of approximately 4mm. The thickness of the headrest is approximately 5.5mm.

 

A quick bit of maths, to ensure the same relative head position, subtract the thickness of the Airfix seat from the thickness of the ejection seat headrest, approximately 4mm.

 

Either I'm roughly correct, and the seat was indeed moved aft of the angled bulkhead, or I'm completely missing something.

 

What I'd like to do is get in the cockpit of an ejection seat equipped vampire, with a tape measure and work our relative positions (or see for myself if there is a cut out in that bulkhead). 

 

Ooooooo lovely Ben looks very interesting,  I am eagerly awaiting your FB.31 conversion bits.  The seat and cockpit floor and bulkhead looks very nice too, great work. 

Chris

[gingerbob]

I can't get the images to load, but this page might be worth trying:

https://www.primeportal.net/hangar/luc_colin/vampire_j28b_walk_2.htm

 

Here's a pretty good photo:  (source: https://www.gengriz.co.uk/2016/nov16.htm )

Edited October 13, 2022 by gingerbob

[Julien]

This FB.6 without a seat shows how far back the rails etc are.

 

 

We have an extensive walkaround section here and its surprising whats there.

[wellsprop]

Thanks @Julien I overlooked that FB6 - great image!

 

I've overlaid that image with a plan I found online, as well as the Venom drawing from @canberra kid and the cockpit I have modelled myself. It is clear that the seat rails are behind bulkhead 2 and they are angled more steeply.

 

Trying to draw more precise conclusions than the above is difficult as I'm unsure of the accuracy of the plans, the provided Venom illustration, and the photo will add parallax - but all these things aside, for the purpose of a 48th model, the conclusion still stands.