Cdr Drysdale was in command of the submarine when it grounded
A nuclear submarine commander whose vessel ran aground in the Red Sea has been reprimanded by a court martial.
HMS Superb damaged its bow and sonar equipment, resulting in it having difficulty diving, in the incident in May 2008.
Cdr Steven Drysdale, from south Wales, admitted an offence of neglecting to perform his duty.
Officers Lt Cdr Andrew Cutler and Lt Lee Blair were also severely reprimanded for their involvement.
Cdr Drysdale pleaded guilty to "failing to ensure the safe direction" of the submarine, while officer of the watch Lt Cdr Cutler pleaded guilty to "failing to supervise the plot officer adequately".
Lt Blair, the submarine's navigation officer, pleaded guilty to "failing to take into account all the dangers in or near the planned movements of HMS Superb".
All three of the officers are still serving in the Royal Navy.
The submarine, which came into service in 1976 and had been based at Faslane on the River Clyde, was decommissioned in September 2008.
The Ministry of Defence said the accident had not led to the submarine being taken out of service earlier than already planned.
The sentencing took place at the HMS Nelson court martial centre at Portsmouth Naval Base.
The hearing heard that the three officers had failed to notice on a chart that they were heading towards a pinnacle that rose to 132m as the submarine travelled in about 1,000m of water in the Red Sea.
Cpt Stuart Crozier, prosecuting, told the hearing that when the submarine collided with the pinnacle, the vessel was brought to an almost immediate halt.
It had to abandon its planned deployment but was able to return to the UK under its own power, the hearing was told.
Cpt Crozier said: "The submarine collided with the underwater obstacle reducing its speed from 16 knots to three knots in a very short time.
"There was a significant amount of damage to the forehead of the submarine but no casualties."
HMS Superb was scrapped by the Royal Navy shortly after the incident
The hearing was told that new procedures had now been brought in by the Royal Navy meaning that all depths had to be rechecked when a new route was charted for a submarine.
Cdr Alison Towler, representing Cdr Drysdale, told the court the commanding officer, from Miskin, had since been moved to a desk job.
She said Cdr Drysdale, who has served in the navy for 25 years, had inspected the chart but had misread the depth of the pinnacle as 723 metres rather than 132 metres.
Cdr Drysdale and Lt Cdr Cutler both expressed their remorse and regret over the incident.
Cdr Stuart Wright, representing Lt Blair, said the navigation officer was "fatigued" at the time of the crash having lost his signal communications officer to illness.
He said that since the incident Lt Blair had been involved in officer training at the Britannia Royal Naval College but would be once again taking up a post of navigation officer onboard the submarine HMS Turbulent later this month.