Bae P103 Swivel mechanism

[uk 75]

I am trying to find out more information about the BAe P103 swivel mechanism for
the engines, as it is not clear from the published drawings how this would have worked.
The models are all in inflight position. I would like to get two distinct models made,
but it would be helpful to see how the arrangement looked

 

[hesham]

My dear Uk 75,

temporarily what I find,until more search.

 

[uk 75]

Hesham
Thanks for the drawing. Like the general arrangement
drawing in Tony Buttler's book it does not show what the
hinge looks like and where it swivels in the wing.

 

[Sundog]

My guess is it is rotating at the location of the front main wing spar.

 

[AndrewN]

Found this drawing, hope it helps.

Cheers

 

[uk 75]

Thanks for this GA drawing which does show the location of the engine swivel on the wing but deliberately hides what the hinge mechanism looks like.

 

[shedofdread]

The 103 has always fascinated me and I believe I have seen all the published images [but would love to be proved wrong....] and have never seen the detail you require. I suppose it's possible that the Heritage Group might have more detail??? Really must get around to building a flying one some time - it's crying out for it.

 

[iverson]

I've been curious about this design since I first saw it. How would it handle loss of an engine during take-off or landing?

 

[shedofdread]

Lose an engine ...and join the Ejection Tie Club!

 

[galgot]

Maybe a solution would have been to have the engines having some degree of lateral swivel movement too, combined with automatic computer control. If it detect one engine fail, it would direct the remaining running jet blast to a more centered position with constant corrections and land it (fast)… But then all that would be heavy maybe.
Still, would have made a nice plane.

 

[_Del_]

It's not as though the Harrier had engine out options at take off either, but asymmetric thrust would make it hairy quick.

 

[iverson]

I suspect that asymmetric thrust would make control impossible and ejection problematic at best. I doubt that computers were up to the engine-management task at that time--things would happen fast. And even if computers were good enough, how would you deal with the inertia of the moving parts in the time available?

 

[Silencer1]

Nice aircraft!

We have at least one example of successfully flying VTOL with the jet engine pods completely rotating and mounted on the wingtips - German VJ-101 (https://www.secretprojects.co.uk/forum/index.php/topic,964.0/all.html)
So, the designers could solve the problem of engines' attachment to the wings, although such solution would also costs weight, complexity, safety issues.

From other hand, V-22 Osprey, is another example of using thrust of engines, located on the wingtips, this time with propellers.
Have been any flying disasters due to engine's malfunctions for this bird?

 

[AeroFranz]

In the V-22's case there is a cross-shaft. No such thing possible with turbojets, AFAIK. Although the Grumman G-698, using special turbofans, was provided with one.

 

[uk 75]

The VJ 101 and the earlier US Bell design
both have the engines pivot at the end of the
wings like the Osprey. The P 103 seems to pivot
from the leading edge of the wing, a much harder
thing to do.

 

[Mike Pryce]

The nearest pic I have to the hinge is the services going across it. As they wanted to keep the engine accessories out of the nacelle they used hydraulic pumps to get power, transferred it across the hinge as shown and then to a hydraulic secondary power system drive in the fuselage.

I got this pic many years ago and never looked at it since. Hope it is of interest. I will see what else I can dig out.

The P.103 was offered to the RAF at a time when its senior officers had trained on the Gloster Meteor and Canberra, both of which had asymmetric engine-out issues that led to crashes and pilot losses. Asking pilots to risk this in the hover was asking a lot.

 

[uk 75]

Harrier
Thank you for this very interesting new picture.
The engines would have been almost flush
with the wings as shown on the models.
Though a small line would have been more
realistic.

 

[Mike Pryce]

Best I can find, from an old photocopy.

 

[Mike Pryce]

The P.103 has been widely publicised for over 30 years, but it never ceases to amaze me how no one took a hard enough look to say, 'OK, maybe not' at the time, and it is still of interest all these years later. Failing symmetrically is a good idea (from 1.00):

https://www.youtube.com/watch?v=1a8xCG7B86Y

Bill Bedford was in the bar soon after. Not possible if you flip over.

 

[uk 75]

Harrier
Thank you for the engine mounting drawing.
As you say, it is amazing that the project got
as far as a mockup. It looks cool in the artwork
but I cannot imagine a pilot walking away from
an engine out.
I may try and get a model made though.

 

[GTX]

I wonder if an automatic ejection system (similar to Yak-38) would work.

 

[red admiral]

I wonder if an automatic ejection system (similar to Yak-38) would work.

Probably, or on engine failure rotate pods to forward flight position. Bear in mind that P103 was STOL as well rather than VTOL so you've still got a wingborne lift component. Would it be any worse than engine failure in a conventional aircraft?

 

[Silencer1]

Probably, or on engine failure rotate pods to forward flight position. Bear in mind that P103 was STOL as well rather than VTOL so you've still got a wingborne lift component. Would it be any worse than engine failure in a conventional aircraft?

When VTOL is in hovering mode the wing lifts almost nothing, as there were no horisontal flow over their surface (which produced lift).
I seen the documentary with Yak-38 crash... It was a matter of seconds, between the engine failure and automatic ejection of pilot.
So, I wonder if the P103 in vertical take-off or landing procedure could transfer engine to STOL configuration - I suspect, to horizontal position (and this also decrease vertical thrust as well) in a period of time, request to achieve a needed airspeed. Even aircraft with thrust to weight ration above 1.0 should spend a time to boost itself for take-off airspeed.

P103 is a nice conception, but now to me is more obvious, that it's just another interesting configuration studied, among many others, of VTOl aircraft.