Ejection Seats

[MightyGem]

Just been reading about the MB16A that's going to be fitted to the Typhoon and JSF/JCA. Apparently it can cope with a 17 stone pilot. Porky!!!

But I digress. The Typhoon jettisons the canopy, while the JSF blows the transparency with MDC. What influences the choice? Is it a manufactures decision or a customer option? Is one better than the other?

[Arm out the window]

What about just going through it?

[Safeware]

M_GApparently it can cope with a 17 stone pilot.

They saw BK coming :ooh:

sw

[jimgriff]

The Mk 16 was designed to cope with a "wider range" of body weights and sizes. Whereas the older seats had quite a narrow margin of userability.
The technology used in the rocket can sense what it is pushing out and adjust thrust to give the same end result and envelope of operation with very small (female) and very large (porky males) (OK and porky females) occupants. The seat also has unique sizeing capabilty (stretch) to accommodate the different heights of occupants. It is a great bit of kit and extremely capable. It takes ejection seat design to a new level. It is also extremely comfortable. I know, 'cos I have sat on one.

Canopy jettison or through canopy is a matter of design. Through canopy tends to be quicker but does have its downside (MDC splatter etc). Type of a/c and operating environment and capability also have a bearing on which system is used. VSTOL a/c tend to have a through the canopy system due to the possible high sink rate of the the a/c in an emergency and the ability of a rocket assisted canopy jetison system being degraded by that situation.

[jimgriff]

The Mk 16 that is going into the JSF is very different to the Mk 16A that is fitted to the Typhoon. There may be many similarities in the design but to look at and operationally they are chalk and cheese.

[John Farley]

MightyGem

The weight concerend is not the nude weight. You might be quite surprised if asked to hold the full AEA handed to you in a lump. Second thoughts refuse if you value your back.

[MightyGem]

Apparently it can cope with a 17 stone pilot
According to Aviate, that is the nude weight. Whatever happened to dress to survive, and not for action! :}

[[email protected]]

Good job they don't use them on Lynx, that'd be Sumo Flight left back at base. :}

[John Farley]

In the days when I used to dial in my weight (to get the rocket thrust line through the actual CG of the man seat combination) it was your weight ready to get in.

It may have changed - but difficult to see how/why unless the CG range that can be tolerated on the seat concerned is so great that it can cope with the variation due to the type of AEA in use. I suppose it is possible that the AEA weight is today accepted as a constant in which case you would still get a considerable variation in man/seat combination when considering L plus C compared with H plus C

[ARINC]

Removing MDC will be quite a relief to anyone who's had to duck under a Tonka as the crew close the canopy, pins in or otherwise. Quite a few instances of the mechanism fouling something with subsequent premature BNNAG !!.

[Blodwyn Pig]

i don't remember ducking out of the way on Tornados, but it was SOP on Hawks to duck out of the way whever the canopy was opened or closed sans pins.

[ARINC]

i don't remember ducking out of the way on Tornados, but it was SOP on Hawks to duck out of the way whever the canopy was opened or closed sans pins.

Well my memory is pretty clear...

[Elmlea]

i don't remember ducking out of the way on Tornados, but it was SOP on Hawks to duck out of the way whever the canopy was opened or closed sans pins.

It depends on how the MDC is triggered. I seem to remember that when you pull your Hawk seat handle, the seat fires and starts heading up. The MDC's only triggered by a lever that was attached to the MDC firing unit which rests on a bar on the seat; so when seat goes up, bar goes up, lever is pushed, MDC goes bang.

Hence, if you were loading up with kit for a transit or something and had a jacket crammed behind you, then if a sleeve was resting on the little bar on the seat the lever on the MDC firing unit would be triggered as you tried to shut the canopy.

No idea if a similar trigger's used on Tornado. I know Tucano studes are taught to warn the groundcrew and close their eyes before shutting the canopy, even though there's no such trigger and no apparent way for the MDC/LCC to spuriously go off. Presumably just a good habit to get into either way!

[engineer(retard)]

I recall that a few Tonkas had the MDC fire on closing, hence the hiding. I think it was due to the length and lack of rigidity of the canopy allowing it to distort in crosswinds and strike the firing unit.

regards

retard

[BluntM8]

I know Tucano studes are taught to warn the groundcrew and close their eyes before shutting the canopy, even though there's no such trigger and no apparent way for the MDC/LCC to spuriously go off. Presumably just a good habit to get into either way!

Yeah, but who actually closes their eyes anyway? :)

I never did, do you?

[PPRuNeUser0211]

Think it's just the groundies are supposed to turn away...

believe for the crew it's just mask and visor....

[Megaton]

Believe golf clubs could also occasionally foul the MDC firing mechanism!