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· A short fat well off crap cave diver. Likes wrecks
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As some of you know Andrew and I went off to Darhab Egypt to for fill one of our diving ambitions and do the infamous Arch dive at the Blue Hole. I put together this little report based on the build up and the big dive just to give some idea of what was involved.

On Saturday 3rd January 2004 at 9.25GMT  Andrew Phillips and I shook hands at 102m just outside the Arch entrance to the Blue Hole. It was big, it was clever and we are suitably smug about it J

So I turned up at Poseidon dive centre and spent the usual first few hours fafing about kitting up my wing on to a twin 12ltr Ali twin set blown to 200 bar with air. I then got a few strange looks from the dive guides as I proceeded to blow off 150bar of the 200bar fill prior to the dive. I then added 1kg to my normal 4kg and headed off to the dive site.

First dive on the rig was on the Eel Garden at 20m I went in with 50bar and came out with 15bar after 33mins. With absolutely no air in the wing and the dry suit I could hold 6m but 2m was not possible and I just popped up from there.  I decided that that was acceptable and made a note to stay below 3m if it all hit the fan.

Next build up dive was in the Canyon to 50m with Andrew. We had twin 12s of 24/20 and two steel 10ltr stages with 36% and 80%. This dive was pretty easy and although the Canyon was an interesting way of getting to 50m with its small entrance at 18m and exit point down at 50, I thaught the dive was a bit dull once you got to the bottom. This dive made you realise that a dry suit was essential and that trim and balance with strange kit could make deco very strenuous and uncomfortable. I was rolling to the right all the time and perversely Andrew was rolling left

Sumiko our 5ft 1” Japanese lady guide demonstrated the grace inherent with her 5000+ dives whilst Andrew and I wiggled and jiggled our way through deco trying to get comfortable.

Next build up dive was the Bells planned at 80m. Gas 15/45. This involved a hike with all the kit to the entry point and our first experience ever with three 10ltr deco stages. We had surface cover and back up deco gas on an emergency yellow blob signal arranged and a fixed time to be sending up red bags to signal all OK. These were overkill for this dive but essential for the Blue hole. The dive plan was a pain in the bum. The entry point was through a small crack in the coral and then into a cave at 15m exiting at 40m. The cave was very tight with all that kit on and a decent rate of 2.5m / min was planned to that point. Unfortunately you cant plan a slow decent on manual tables so we used lap tops to do the job but they were then limited in how you got from 40m to 80m to a fixed 2.5m decent rate L We planned for reaching 80m on min 8 and doing 10min at 80 and ascending to 60m for 10min at 60 prior to ascending for deco on the coral wall.

In the event I was being pitched forward by the three 10ltr stages and was struggling to maintain trim so we aborted the cave section as that was a headfirst decent. At 15m we did a kit check and a crack was found in Andrews’s wing inflator that was leaking gas and my back up reg was leaking from the Din fitting. We decided to continue with the dive as we had the third stage of air for bail out (it wasn’t in the deco plan) the leeks were small and Andrew had a redundant bladder on his wing.

We dropped quickly to 80m and I had just levelled out when I was hit by a dizzy spell. I swapped to my necklace back gas reg in case I had the wrong reg in my mouth and got close to the wall. I looked at my VR3, which said I had 12mins to the surface, which included ascent, and this was a big comfort, as I knew I could abort the dive quickly. Having focused on the rocks and my computer the dizziness went away I don’t suppose the whole thing lasted more than 10 seconds and it was probably narcosis due to the END of 35m. I checked for Andrew who was right beside me and I looked for Joe the guide but he was well above me so I couldn’t find him.  I decided to carry on so having confirmed that I had had the correct reg to start with I swapped back to the primary reg and began looking for Joe in earnest. Eventually rolling on my back I spotted him about 6m above me and slightly behind. He signalled OK so I started off again.

At 18mins we moved up to 60m for the planned 10mins but we ended up cutting this short as I was down to 80bar and Andrew was on 90. I had dropped to 50bar after a leisurely ascent to 40m with a deep deco stop at 52m safe in the knowledge that my Air reg was clipped off to my chest D ring.

The rest of the dive went without much incident Andrew had fun and games with his SMB launch due to the crap reel he was using but apart from that it was a good dive.
Andrew was really buzzing after the dive but I had had quite a stressful time and I also had sinus pain and tingling in my face so I was having a bit of a fitful evening deciding whether or not I was bent.

I did two single tank 20m Nitrox 36 dives the next day having decided that any pain that could be sorted in one night with two aspirin was definitely not a bend J

The big day arrived and Andrew and I will openly admit to being more than a little nervous. I had reconfigured my weighting by moving the canister torch down to the bottom of the twin set in an effort to get better trim. Andrew appeared happy with his rig so went as before having repaired his wing inflator. My leek turned out to be a bit of grit embedded in the O ring so no problems there. Following my dizzy spell and with due respect to the planned 100m depth we opted for 13/65 trimix with 21/25 travel gas and bail out. Deco gas was to include the 21/25 and the standard 32% and 80% 02.

The plan was to enter the Arch at 60m and go through dropping to 90m hugging the left hand wall. Having got through the arch we were to move over to the right hand wall get final OK’s all round and descend to 100m for 2mins. Our bottom time was limited by the twin 12ltr tanks and puny 200bar fills. At 100m we were gulping back gas at the rate of  220 lpm on a 20 SAC so twin 12s at 200bar gave us apx 22mins total of gas supply with a 50 bar reserve to get from 60m to 100m and back up to 60m.

We kitted up and surface swam out to the top of the Arch exchanged Ok’s and dropped to 30m. for a bubble check. It was Joe’s turn to have a problem with a small stream of bubbles coming from his wing inflator of his CCR. He decided to go with it and as he had over 7000 dives and a dry suit for redundant buoyancy we didn’t argue with him.

We all dropped to 60m and prepared to enter the Arch. We switched from 21/25 travel gas to 13/65 back gas and I was pleased to be in perfect trim and clear headed. Andrew had a problem with the gas switch on his VR3 and the dive was halted whilst he sorted it out. He got a bit frustrated and we didn’t know why at that stage so there were a lot of Oks and confidence checks going on before we entered the Arch.  We passed through following the comforting blue light at the end of the tunnel and I looked back into the inky black of the blue hole and realised how easy it was for a diver to panic and lose it with solid coral overhead blackness behind and the need to drop and drop down to 80 –90m to get through the arch. I knew in my hart that it was at this point in the dive that so many had died attempting it on air or single tanks.

We hovered at 90m at the exit and did final Ok's before dropping to 100m. The END of 20m on 65% He was very comforting and it was incredible to be able think that clearly at 100m. Andrew and Joe spotted a couple of sharks down at 120m but they finned off before I turned around. I finned over to Andrew and we shook hands and turned to look back at the arch one last time before heading up to out first 1min deco stop at 82m. Setting off up the coral wall I looked up to see an underwater mountain
stretching away above me as far as I could see. Below me the seabed was apparently over 1000m down and the inky blue gave way to black some 30m below my position.

As you would expect the coral at this depth was untouched and beautiful with delicate fans extending perilously out form the shear wall surrounded by darting iridescent red fish. I was in heaven. Once again Joe backed off and let Andrew and I continue the dive alone whilst he watched from above. We ascended to 60m and gas switched to 21/25 for deco with 60bar left in the twin set after a mere 17mins below 60m  

Next deco stop was 52m and a quick check on the computer showed that we had to hustle on up to 40m by Min 23 to deploy the SMBs and send the we are OK signal to the shore cover.

Gas switch to 32% completed and SMBs safely deployed we settled in to our 1 ½ hour remaining deco by studying the reef or hovering out in the blue, as was our want. The reef outside the blue hole is lovely but for me the thrill of hovering in the blue was the best way to wile away the minutes you could stare into oblivion and lose all sense of reality.  This was what it must be like to be in space. I padded all the shallow stops from 18m up by an extra two mins and the 9m 80% stop by 4mins this reduced the 6m hang from 45mins down to 33mins.

We crossed over the saddle with 6mins of deco left on the computer. I cleared my VR3 and added 5mins at 6 and spent a further 10mins ascending to the surface.

I exited the water feeling positively elated no sinus problems or tingly bits and just big grins all round. It was truly the best dive I have ever done.


Mark Chase
Back Gas Twin 12’s 13/65 Trimix
Travel Gas Single 10 ltr 21/25 Ali tank
Deep deco       As above
Intermediate Deco Single 10ltr 32% Steel
Rich Deco Single 10ltr 80% Steel

Table bail out Deco:

Hopefully Andy will insert this as it was on his laptop

Gas cost for three trimix dives including deco Nitrox mix £332

Dive included one assistant (AOW diver) and one qualified Trimix instructor as surface cover. We were not charged for the unused drop tanks.

Many thanks Jo Davin for leading the dive and his assistance in dive planning and to Poseidon Dive centre for allowing us to have a go and all there friendly and qualified assistance with kit issues. Note that Poseidon has a He analyser on site, which I would consider essential for this type of dive.
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· Registered
12,750 Posts
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Another good write up Mark.

I can't comment any further as this kind of dive is way outside my experience (but not desire). I know the site has claimed many divers, it seems crazy to try on singles and air, yet they do. The downside of good vis making people over confident.

At £332 for gas, a CCR comes to mind

Nice one


· Exiled in Scotland...
6,245 Posts
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<font color='#000080'>Wow, That sounds Fantastic. I think I'll have to work on my diving to get up to the standard you are at. Perhaps by my next re-incarnation I'll have enough dives and experience to do something like this.

Dave C
BSAC OD flip all dives

· Just not enough dive time.
9,000 Posts
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Nice report Mark, what's up with your spelling mate, hardly found any wrong-uns you still on the back gas?

Not my sort of dive but glad you and Andy enjoyed it so much, bit costly thought at 332 quid - each? Or for all of you?

So 18m at Stoney is going to look a bit tame?


· Registered
12,115 Posts
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Top form, those men!

A genuinely spectacular write-up and experience lads! Very well done and a true achievement, by anyone's standards! Prooves the 7 P's adage, what?

So what next? Same gig again on CCR?? Glad you're back with us safe.


· Grumbler-chief in Residence
1,921 Posts
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Well, I now formally hate computers, those that know me will realise that this is a mute point, I already hated them.

Mark and I had subtly different dives, I just want to add a point before I get into it, Dahab is a great place to be, I have dived all over Egypt, this was the first time I have been to Dahab, I loved it. So much less intense than Sharm, shore diving with a family around works out great, my partner (Lizzy) likes to do one dive a day, we could go for a dive, and then meet up with the partners / children and then all dive together for the second dive. The exception to this was the bigger dives where a second dive was out of the question. Marks wife is mad, she took herself and the childern off to Cairo to see the Pyramids, it takes a certain determination to subject yourself the the 14 hours in a car that are required to do this. Having said that they all had a fantastic time. Added to this Mark rode a horse, it is possible that 2 days later he might just be walking in a style that approaches normal, well normal for Mark that is!!!!!

The dives,

There are various sites in Dahab that are worth a visit, for shallow dives the best of these is probably the islands, the outside of the Blue Hole is very pleasent also.

The bigger dives, I will skip the 50M dive, Mark has pretty much said all that is necessary, an enjoyable dive but not much more to it.

The Bells, this for me was the dive of the trip, dispite a bit of a leak I felt very comfortable on this dive. Drop in thru the coral out and pause, once all was settled, I stuck my feet down and went for it, I love that feeling, when you just drop straight down and you can feel your fin tips kinda flutter, straight to 80, hit the brakes at about 70 takes 10M ish to stop, check the computer, snicker quietly to ones self and dip an extra 1M just to get one up on Mark. Mark the miserable sod, knew I would do this and nicked another half a meter............bugger.

I find it hard to discribe this dive to others, once we had got to 80, I turned slightly to my right and kicked off towards the wall, I looked up, and stopped stone dead, what confronted me was one of the most awe inspiring sights of my life, a wall of rock and coral that is beyond my abilities to discribe. All I can say is, if you have ever seen a mountain range and can remember the feeling that such stunning scenery left with you then you have an indication of how I felt. I stayed there for what felt like an eternity, but was in reality about 10 seconds, and took a second kick towards the wall, at this point I glanced down. OH MY GOD, such incredible beauty, the ground sloped away from the wall into the favomless depths, dotted on it were dark patches against the light of the sand, it reminded me of a pattern generated by the kalidoscopes that a lot of us had as children. From this point on I was mesmerised by it all, the delicate black corals with there attendant goldfish, once we reached the relative shallow depths of 25M, just how vibrant the colours became compared to the deeper parts of the dive. This one will be with me for some time to come.

The Arch, to be honest this was Marks dive, he enjoyed it as much as I enjoyed the Bells. mine is a story of anoyance. To start with we driopped to 30M paused to check each others kit, Joe had a leak, Mark did his best to sort it. It was there but not too bad. Down to 60M to the first gas switch. Joe had called for a stop here, he wanted to be certain the Mark and myself were OK and settled to go thru the Arch, fair enough I say. Well the VR3, it has a mode called DVO, this allows the diver to change certain parameters during the dive. It is the same button you use to do a gas switch, I have used the VR3 5 times before this dive, it bit me. I pushed the button, straight into DVO mode, could I get the buggering thing back out, could I f**k. I pushed pulled prodded and even considered stamping on the damn thing, eventually I got it to switch, I will know what to do next time, I promise you. It turns out both Mark and Joe thought I was in some kind of trouble, not true, I was just bloody well getting pissed off.

To be honest from this point on I felt like I was chasing the dive, I am going to go back, I want to go there with a lot more gas and take my time, I feel like I missed it. That being said, I am truly pleased for Mark, he had a cracking time. I am not saying I did not enjoy it, I did, I just felt like I wanted more time. We have done it though. The Arch at the Blue Hole in Dahab, one of the most famous dive sites in the world.


Take care,


The pre-planned profile DecoPlanner set to 20 low 80 high;

 60M - 3 mins - 21/25
 80M - 3 mins - 13/65
 90M - 2 mins - 13/65
101M - 2 mins - 13/65

Gas planning;

10L - 21/25 - 1118L - 162 Bar
24L - 13/65 - 2291L - 145 Bar
10L - 32%   - 775L   - 128 Bar
10L - 80%   - 854L   - 135 Bar

All planning was based on rule of thirds, plus a bit.

The dive n deco;

60M - 3 mins
80M - 3 mins
90M - 2 mins
101M - 2 mins
57 - 1 switch 21/25
50 - 5 (this included 4 mins because we could)
39 - 1 switch 32,  Bag off
36 - 1
33 - 1
30 - 1
27 - 1
24 - 1
21 - 1
18 - 4
15 - 4
12 - 7
9 - 8 switch 80
6 - 35

We flew the VR3's, we changed the dive a bit, they are a god send. Those without them who wnat to do these dives. We love them, you make your own mind up.

· Registered
1,211 Posts
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Well done chaps. Nice report.  Good to have you back safe and sound.

You can now use the phrase one of my USA buddies once used....

"80m dive....pah, I've done deco deeper than that"

Very stylish....


· Banned
1,775 Posts
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Thanks Mark, very interesting.

By the way, I've had a short period of dizziness like you describe twice.  The general feeling on here was that it was a slightly bunged up eustacion (is that how you spell it?) (...and I'm asking you for spelling tips???!) tube equalising at a different time to the other.

Did you have a slight cold or anything?

· Ginger, Irish, sometimes stroppy
5,898 Posts
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Nice one guys, I have done the same sites but not to the same depths and totally agree....Dahab is a wonderful place. I loved the Canyon and the 'Bells to Blue Hole'. My favourite moment was sitting blow the chimney of the bells and having blue in every direction except the wall.

I just happy to see the level of preparation you guys put in to make it happen, after seeing the Plaque for the guys that didn't make it above the blue hole, I have a lot of respect for divers who take the risks seriously.

Hats off


· Creature of the night
14,153 Posts
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<font color='#000080'>Mark/Andy

what a fantastic achievement guys, glad you are both ok.

What is your next goal then

Safe diving,

· Registered
18,471 Posts
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Great report....almost makes me want to do it, even though I am not a depth fiend in the slightest.  Just to see the untouched coral, and have that "infinity" experience.

Really, really glad you are back safe and sound, above all though.

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