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Quote:

Originally Posted by Arthur Bellcrank (Post 10788857)

Yes I remember Tony Downie at Blackpool and met him again at Exeter.
I flew in YF about a week before it was withdrawn from service, it was one of the ex Malaysian 400 series that was brought back by BAF in the late seventies, very heavy aircraft, we carried out a weight reduction programme at JEA when it was converted to a freighter, we found a 2 inch loom running along the leading edge, couldn't work out what it was, it transpired that it ran to loudspeakers that were once fitted on the wingtips. The RMAF used to fly over the forests broadcasting propaganda.
Useless information snippet for today.

Tony used to give us a hand on pretty much all the Herald checks as he knew the NDT side of the aircraft like the back of his hand.
I've no idea if he's still with us, the last time I saw him was about 18 years ago.
Nice story about YF, don't mention it to Boris & Co. it might give them ideas :eek:
Was the Herald flown at a reduced altitude / pressure differential later in life ? I seem to remember reading something about it.

The original Herald used a spot welding technique to attach the lower fuselage skins to the stringers, the process in fact removed the surface protection of the skins and subsequent corrosion lead to a crash with fatalities in Canada. A second crash led to a report of corrosion problems and the max diff was reduced from 4.2 psi to 3 psi on aircraft up to 6 months old, to 2 psi on aircraft between 6 months and 12 months and zero on aircraft above 12 months.
The method of manufacture was amended to used conventional rivets and an expoxy finish to the internal skins, following this the max diff was set at 2.2 psi, in actual fact on the freighters this was difficult to achieve, the impinging rails around the rear cargo door frames were regularly damaged by the fork lifts and caused leaks.
At one time Channel Express had contracts to fly day old chicks from UK to Valencia, but suffered fatalities due to cabin altitude, the engineer with the aircraft used to use damp rags and caulk around the door gaps in flight to raise the max diff. The return flight carried exhaust pipes for Ford, either to Cologne or Speke, another useless snippet.

The lower structure also incorporated strontium cromate wicks which ran laterally across the skins and stringers, but in later years due to health and safety this was removed and the areas were hand cleaned every hangar visit (6 months) and dewatering fluid was used.

Thanks for the info Arthur,
Come to think of it, the subject of the reduced differential came up during an internal belly skin inspection.
I only did 3 or 4 Herald checks so I'm no expert on them, but I'm pretty sure I still have a scar on the back of my head caused by a sharp split pin whist crawling under the flight deck floor !