G109 grounded
 

The RAF has grounded its fleet of G109B Vigilants. Word on the street is it is following an incident with a civilian one. Anyone know what happened?

Tim

May be something to do with this

"Following a recent engine failure, the BGA strongly recommends that whenever the valve clearances are checked or adjusted on the Grob G2500 engine, the engine is turned to fully open the valve and a check carried out to ensure there is clearance between the rocker arm and the valve roto cap. If you are affected, please pass this instruction on to your maintenance engineer."

That's all I know.

Cheers

Also an EASA AD concerning the elevator control rod.

TM

It is the elevator issue described above.

BBK

Thanks, I'll go and read the AD!

Tim

Why would they ground a whole fleet for an AD that only requires periodic inspection of a specific part? Can't the RAF simply comply with the AD requirements?

AIUI, it requires a modification to the vertical stabiliser to allow access for the inspection.

The guy who knows is Tim Dews of Airborne Composites in the UK; I believe he identified the original problem.

Edit - I was wrong; the access mod for inspection is for a different issue. Sorry if I misled anybody.

DG800 - The RAF can't take any risks as they are flying someone's kid in the Grobs and after the summer a couple of years back they are over safe with good cause.

Can you imagine the uproar if one did go in and the fleet hadn't been grounded? The fleet are dispursed around the country and it takes time to get the manpower in the correct place.

May be an over reaction but better that than learn from hindsight.

OB

It already happened before in about '91. The entire fleet was first grounded, (after a very nasty incident at Binbrook) then the restriction was partially lifted to allow cadets to go solo - with an instructor along 'just in case'!! It was called a 'ghost solo'.
I think it was caused by the use of MOGAS, combined with long periods of carb heat causing vaporistion in the fuel lines, but maybe someone else can elucidate.
(NB It does strike me as strange that a powered glider losing its engine can be considered dangerous)