here is what would likley happen
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To: u-53
From: BdU
Message Received and Understood. wounded? medical needs? Please have your Chief Engineer compose a detailed list of the minimum equipment which in his opinion, if repaired, would enable the boat to travel under it's own power. Transmit your requirments to us as soon as possible. avoid detection at all cost, keep radio transmissions to a minimum, and remain submerged if possible. Check in at 10 hour intervals. Upon reception of your chief engineer's requirments we will send U-202 with machinists, tools and parts as he is schuled for departure late tonight.
good luck!
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when U-202 arrives, the mechanics would take a raft over to your boat, assess the situation and then have tools and parts brought over from U-202.
U-202 would remain in position until your boat was able to move under it's own power at which point U-202 would head out on its normal patrol, and U-53 would return to base with mechanics, tools and parts.
when you dock... if your base is not where U-202 originated, the mechanics would likley dispatch a truck to carry them and their equipment back to their base by road.
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