As soon as I heard that the football team and their coach had been found alive but trapped at the far end of some pretty long underwater passages, the fact that the longest dive previously required to get hitherto non divers out of a flooded cave in the UK - Sleets Gill in Yorkshire, March 1992 - was 100m to an airbell, followed by a further 20-30m, made me realise that diving these youngsters back out again would require going against all accepted best practice in cave diving manuals and potentially risking losing one or more along the way. A very difficult decision to have to take.
However, there was little doubt in my mind that waiting for the monsoon rains to come in force would have been allowing nature to take the decision for you by effectively completely submerging most, if not probably all, of the cave system for months on end. If such happens during the monsoon period then there would not even have been bodies left to recover afterwards.
So, after collecting my thoughts, I telephoned Reg Vallintine of the Historical Diving Society to pick up on a plan I'd proposed for evacuating a seriously injured caver from the Daren Cilau cave system near Crickhowell in South Wales, in the event it wasn't going to be possible for the casualty to assist with the rescue operation during the exit haul through the very tight and twisting 520-m long Entrance Series. The alternative was to dive them out through a 575m-long sump, at depths of up to -22m, safely wrapped up in a pressurised capsule, breathing from a self-contained supply of air for the duration of the dive.
(If Channel 4 TV had properly qualified documentary commissioning editors during the mid-to-late 1980s then you'd have heard about this on network TV across the UK, along with Channel 4 today having film footage of Rick Stanton and Ian Rolland in action at the cutting edge of British cave exploration, through the proposed drama/documentary film*
LlangattockMountain - Searching for the Secret River.)
As things turned out, Reg wasn't in and so I had to leave a telephone answerphone message mentioning the diving escape capsule idea. The same evening, another member of the society told me that the name of the apparatus I was enquiring about is the Hyperlite 1 portable hyperbaric chamber -
http://www.sosgroup.co/product/hyperlite-1-portable-hyperbaric-chamber/4 - which I checked out online and, realising the amount of modification required for cave diving without ripping the hoses away from their connectors, ensuring the fabric wouldn't be torn by scraping on sharp rocks and protecting & securing the control unit, there just wasn't enough time to turn round a usable device in the few days available.
Well, given the Thai Navy already has two Hyperlite portable hyperbaric chambers, I guess this is where some official in Thailand thought of contacting Elon Musk to see if he could manufacture a suitable device in time . . .
My favoured choice of an escape route was working a way down into the cave from one or other of the surface holes, but it seemed that those on the spot had already realised the diving option was going to give the best and most likely chance of saving everyone's lives.
The reason why the 'suitability' comment has been rather bluntly put forwards in relation to the mini 'submarine' and the tham Luang rescue is that the most tricky part of the diving is reported to have required simultaneously scraping one's chest on the floor and back on the roof of the tunnel (for a normal-sized person) whilst underwater. When you see that most divers wear their air cylinders on their back you'll understand the problem here in making progress through such a tunnel without drowning. Add to this a few twists and turns in short succession and you'll realise that a rigid cylinder will not bend to go round the corners in the same way that a human body can.
However, what Elon Musk has achieved in a phenomenally short period of time is exactly the type of emergency diving escape capsule that would have saved lives had the very long sections of diving also required diving deeper than the 5m or so, which I believe has been the greatest depth required in tham Luang.
So, I hope Elon Musk develops his capsule further and the equipment will be ready and available when it will truly, one day, prove to be life-saving apparatus. He should be applauded for stepping into the breach, working extremely fast under pressure from the monsoon clock and developing an important piece of diving safety equipment which has hitherto been unavailable.
*Sid Perou had agreed to do the filming and Bruce Bedford, who founded
Descent magazine and already had a number of skillfully written BBC radio dramas to his credit, was the screenwriter. The proposed producer was John Ellis of the Channel 4 TV
Visions UK/European cinema series.