Rangoon airport is flat as a pancake - strangely enough like most airports & it is very active. It is a large area too so - where to 'drill'?
The surrounding land is pretty much flat as a pancake.
Anything buried would have required a massive amount of earth shifting. I can not see they would even have bothered trying to do that.
David Cundall is befuddled or a fantasist or trying to scam money.
I did note that PSP (Pierced Steel Planking) is so common in Rangoon it was used in fencing around some of the churches & other buildings. I wonder how long that's been there? So no doubt Mr. Cundall will keep finding that.
The PSP they found...
Spitfire hunter pledges the search will go on - Telegraph