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Old 31st Aug 2005, 21:32
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Tarnished
 
Join Date: Mar 2003
Location: Gloucestershire
Posts: 436
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Soiled Glove,

I posted several times on the Typhoon at RIAT thread worth a read if you have a chance.

I know Typhoon was not g limited during subject event and I seriously doubt this Rafale was g limited either, they would both have been on an alpha limit. To be on the (configuration and mass dependant) g limit a speed of about 400kts would be required.

Typhoon does have an over-ride stop to give a proportion of extra g, but it will not over-ride an alpha limited condition. It is important to be aware that this g over-ride was incorporated in the design a long time before GPWS was included into the baseline design. We tested GPWS in many extreme attitudes (albeit with a false base height set for safety) and it works, it works really well.

The utility of a g over-ride is I believe questionable in light of having GPWS. If you look at the sums the difference in recovery height (or displacement in the avoiding mid air collision case) between what max g will get you and what max g plus x% will get you is minimal. Bear in mind that this excursion comes with a significant penalty to the structural life of the airframe, inspection time etc.

The thought that came to me after watching Rafale video was that maybe these modern "carefree" aircraft are building a feeling of invincibility amongst their pilots? Typhoon is an absolute dream to fly and once you have learnt that you can smash the stick around the box without a care for historical limits you quickly get used to it. We did seriously rediculous series of inputs during the trials - we dubbed it a careless clearance rather than a carefree one.

Another problem these jets have is the ability to add energy very quickly, unload for a few secs and you've added 100kts, which makes a big difference to you turn circle and gate height. I think the Rafale pilot unloaded during his alignment correction just after the apex of his "loop", I believe this was his mistake.

Carefree FCS make life great, but they cannae change the laws of physics Jim (RIP Scotty).

Bubbles, base heights and gate heights are all there for good reason.

Tarnished
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