Airfame limitation

[JP1]

Hi,

Where can I find out information of airframe limitations with regard to hours on the Bulldog.

Over in the mil forum http://www.pprune.org/forums/showthread.php?t=282043 there is a Bulldog listed with over 8000 hrs. A search of the CAA website recently pulled up a doc stating approx 8000 hrs (I can't remember the exact figure). I have also seen one for sale at £36K with 8000+ hours.

Seems that the info I read may be incorrect, since if there is a limitation of this nature then Bulldogs with these number of hours surely have limited value.

Maybe I need more practise navigating the CAA site but it not the easiest site to navigate. Is there a definitive place where this info is held.

JP1

[airborne_artist]

p21 of http://www.caa.co.uk/docs/33/srg_gad_gasil2002_01.pdf says:

"The wing spar centre section joint limits the fatigue life of the Bulldog, and the aircraft must be grounded when a fatigue index (FI) of 114 is reached.

The airframe is however, capable of continuing in service until a FI of 200 is reached, provided the wing spar centre section joint is modified (BAE SYSTEMS modification BH193) to ensure compliance with CAA Airworthiness Directive 004-07-2001."

"Where an [Bulldog] aircraft has never been fitted with a fatigue meter, the wing spar centre section joint fatigue life limit is reached at 5000 flying hours. If the wing spar centre section joint is modified, then the aircraft can continue in service until 8760 hours. All the above information is more fully described in mandatory service bulletin BDG/100/170."

The Dog in question has 8639hrs.

[Genghis the Engineer]

You need to speak to somebody at de Havilland Support Ltd at Duxford - they support the Bulldog and will have chapter and verse.

G

[JP1]

Thanks AA.

I was aware of the wing spar limit for Bulldogs that have not been fitted with an FI meter. The CAA document I read must have been referring to aircraft that were not fitted with one and hence the number you have quoted for the airframe limit of 8760 hours.

It's implicit then that a Bulldog such as the one mentioned above has been fitted with a FI meter, otherwise it residual value of £17K is rather high for 121 hours of remaining airframe life.

I now understand why I see high hour Bulldogs advertised at prices upto £40k

[hugh flung_dung]

PM me if you're looking for a good Bulldog (not ex-mil) with good hours and equipment.

HFD

[Mandator]

Clearly, several people have been looking at the Bulldog currently up for tender at Witham Specialist Vehicles, Colsterworth. Buyer beware. It has accumulated 114.9 FI and has NOT had modification BH193 embodied. I'm not a propeller expert, but like a lot of the other ex-RAF aircraft it might also need a replacement propeller hub and I think the time period for the Hartzell special offer has expired.