Where does this "5 shorts means i am in trouble" comes from?
I never heard of that and cannot find any reference either...
Sound Signals - BoatSafe.com
COLREGS - Rule 34. Since I said (euphemistically) "I am in trouble" I take responsibility for any confusion. Technically it means "I disagree with your intentions." It is also used by many bridges when they are closing as a warning. The appropriate signals for "I am in trouble" are contained in Rule 37.
Perhaps I should have quoted Rule 36 instead...
Rule 36 - Signals to Attract Attention
If necessary to attract the attention of another vessel, any vessel may make light or sound signals that cannot be mistaken for any signal authorized elsewhere in these Rules, or may direct the beam of her searchlight in the direction of the danger, in such a way as not to embarrass any vessel. Any light to attract the attention of another vessel shall be such that it cannot be mistaken for any aid to navigation. For the purpose of this Rule the use of high intensity intermittent or revolving lights, such as strobe lights, shall be avoided
Since 5 blasts is a warning signal it usually "can not be mistaken for any signal authorized."
Drawbridge Opening Signals: The operator of a vessel requesting a drawbridge to open
shall signal the bridge tender, and the bridge tender shall acknowledge that signal. The
following are the most common types of signals a vessel operator should use to request an
1) Radiotelephone Communications - Most bridges monitor VHF-FM channels 13 and 16 with
the exception of bridges in Florida. In June 1996, the FCC published a notice stating that all
boaters throughout the State of Florida should hail bridge tenders on VHF-FM channel 9 to
reduce the high amount of traffic on channel 13. Boaters operating in Georgia and South
Carolina are encouraged to follow the same procedures.
Note: Boaters should always use “low power (1 watt) output” on their VHF-FM marine radio
when hailing a bridge tender.
2) Sound Signals - These signals shall be made by whistle, horn, megaphone, or hailer. To
request an opening, the vessel operator shall give the “opening signal” consisting of one
prolonged blast (4 to 6 seconds duration) followed by one short blast (about 1 second
duration). The draw tender shall reply with the same sound signal (one prolonged followed by
one short) acknowledging that the draw can be opened immediately. When a vessel
approaches a drawbridge with the draw in the open position, the vessel shall give the opening
signal. If no acknowledgment is received within 30 seconds, the vessel may proceed, with
caution, through the open draw. When a draw cannot be opened immediately, or is open and
must be closed promptly, the draw tender shall give five short blasts sounded in rapid
succession after the vessel’s opening signal request.
Fair winds and following seas