That is why free fall lifeboat is safer than lifeboats with two falls and a wire pull to launch from inside the boat.
Get everybody in the boat seated and strapped in, pump up hydraulic pressure and off you go. (unless you forgot to to remove any extra safety sling):
PS> Since there are only one free fall lifeboat there is a requirement for a MOB-boat, which is what this thread is about.
Couldn’t agree more! However I am talking about a rescue boat which requires a davit. In unto itself the davit is pretty darn bulletproof (and even dare I say idiot proof). The cables are tough and can haul many times their weight, the gearbox is tremendously strong with nicely made brass worm gears, likewise the boat rollers do great, davit arms are overbuilt to beat the band. Everything works like a symphony performance when the boat is lowered brake drums are way overbuilt brake shoes wouldn’t really fail for 20 plus years.
Why would anyone saddle this amazing machine with a releasing arm attached to 4 Rube Goldberg-Like plastic encased pulleys led by a cheesy little 1/4” cable in about 5 different directions. Please consider my logic.
I speak fluent dumb and I have a simple answer:
The lifeboats still maintain OEM releasing gear, I am talking about the Rescue boat. It does not make me happy to have to resort to this but I will concede it could be necessary, and if the ship goes down whatever works is a good answer.
True, could someone educate me?
Has anybody noticed that the lifeboat(s) are seldom used in actual evacuations?
Whenever pictures or videos showing the casualty after abandonment are available, you’ll see the lifeboat(s) still in stowed position in most cases. (Or burnt to sinders in case of a major fire)
Another thing that is noticeable is that in many cases the entire crew is lifted off by helicopters in dramatic rescue operations shown on TV News, only for the ship to survive and be salvaged.
#1 would be that it’s safer for the boat crew to lower themselves.
#2 with such small crews why waste a person as designated brake man when the crew can lower themselves and it’s faster for them to do so anyway?
Didn’t get past the first sentence. Easy call to not put additional personnel at risk for a MOB situation. You can cut that 80 knots in half and it would be the same result.
If one of the boat’s crew tends to the wire lowering the boat themselves the wire will not become fouled with anything else.
My observation is that the davits are generally mounted immediately above the propeller aperture, the propulsion is woefully inadequate and the colour coded release under load and no load handles can be confused in the dark with disastrous results.
Earlier this year a New Zealand frigate launched and recovered it’s RIB in conditions that were so bad that helicopters could not be used to rescue a yachtsman. It was hearting to see that the lessons we learnt in a Montague Whaler launched every day at sea without notice under oars haven’t been lost.
In those conditions the so called rescue boat would have stayed firmly lashed in it’s cradle and I would have manoeuvred the ship alongside the yacht providing a Lee.
The rescue boat is not completely useless. Retouching the draft marks and taking the master to town from the port at Papeete it was ideal.
Not familiar with open rescue boats, presumably the remote control wire on the enclosed lifeboats is similar.
There have been problems with this arrangement. A lifeboat was lost from container ship during a drill at full sea speed a few years ago because of a problem with the remote control wire, nobody aboard.
The issue is when the wire spools onto the drum improperly. There is an article here:
USCG: Unexpected Dangers: Lifeboat Remote Control Wires
USCG safety alert here: UNEXPECTED DANGERS: LIFEBOAT REMOTE CONTROL WIRES
Is a Montague Whaler anything like a monomoy boat?
On an enclosed lifeboat the remote control wire will foul on itself on the drum if it did not spool on properly. Is there something different about the arrangement with a rescue boat that prevents this from happening?
The self-releasing mechanism is there so someone can launch themselves in an emergency.
Say the ship is ablaze and a person can’t get near the lifeboats because of smoke etc. and their only means of escape is on the rescue boat, they have to have a means of launching themselves.
It’s hard to generalize about what could be / happen when rescue boat can refer to various things. Is the OP talking about the lifeboat designated as a rescue boat (gravity davit) or a designated rescue boat like @Hogsnort is talking about(hydraulic davit)? On a hydraulic type I have experience with, unlike a gravity davit for lifeboats for a single point lift type rescue boat - the extending the davit function is split from the lowering function. So for emergency lowering from inside the boat:
It’s hard to imagine but not impossible I guess for some one to so poorly maintain the lowering cable reel so that a knot will either jam the reel or not pass through the guide in the assembly.
Not a enclosed lifeboat designated as a rescue boat. In that case the remote control wire is on the davit and is designed to, but sometimes doesn’t, pay out at the same rate as the falls.
This thread is about an open rescue boat remote wire. If the spool/reel is in the hands of a crewmember of the boat it seems like it would be less likely to cause a problem. At least it’s much more likely to be noticed and corrected.
I’ve no experience with using a remote control wire to launch an open rescue boat but not sure if that’s the same arrangement as described in the OP.
From here:
This looks similar to the lifeboat arrangement. The large drum on the left is the single fall and presumably the smaller drum on the right holds the remote control wire.
Yes it seems he’s talking about that type. My info relates to VestDavit PLR types.
Unfortunately the video doesn’t show the emergency scheme in use.
Arrows point to the stowed emer lowering spool.
In the case of the lowering actuating cable mounted on the “auxiliary” spool there would seem no substitute for proper inspection and maintenance.
So is the answer to eliminate the requirement for launching that type of rescue boat from inside the boat? Is it poor requirement or poor design?
Yes the rescue boat has it’s place, and as places go Papeete ain’t bad. But one other point to consider: in the wake of COVID there is a contagious virus of insanity. I can see a situation where someone is desperate to depart but rather than saying anything just drops himself off from the anchorage.
Thank you,
I knew there was something out there!
Our spool is on the davit but it has the same kind of problem, just can’t escape spinning cable possibility of catching something stationary.
The Montague whaler was very similar but with a narrower beam of 6 feet. It also had a centre-case and centre board for sailing. There is a good description in Montagu whaler - Wikipedia.
As a sea boat the whaler was swung out and was suspended on the Robertson disengaging gear. It was a simple system where two cams were kept in position by a longitudinal chain under tension. Three pins, two at the mechanism at each falls and one on the Stenhouse slip were moused in position to prevent accidental release.
Each watch the Leading Hand of the watch reported to the OOW that the boat was off the pins ( there was sufficient tension in the chain) and the boat was free of water. The tiller was lashed inboard with light twine.
Lowering the boat was a well drilled evolution with each person in the duty watch having a designated task as did the boats crew. The boat rope was passed under the forward thwart and held in place by the Sampson post lying across the two thwarts making the boat rope easy to release under load.
Lowering the boat the order “pins out in the boat” and coxswain and bowman removed the pins and raised their hands.
The officer lowering the boat taking into account the roll of the ship and the sea ordered slip and the boat dropped onto the crest of a wave and sheared away from the ship. The coxswain placed the stroke oar in its crutch and paralleled the ship’s course at a distance off while oars were shipped . If it was an MOB downed aircraft the coxswain would allow the sea boat to be towed as close to the position as possible.
On releasing the boat rope the bowman ( whose oar was shorter with the blade facing forward so he didn’t interfere with the other oarsmen) would ship his oar and start pulling with the other four oarsmen.
Bothe the bowman and coxswain would reset their individual hooks by replacing the pin and mousing it. The adjustment of the fore and aft chain left until the boat was stowed.
Recovery of the boat in moderate to heavy seas the ship passed the stern of the boat and backed down hard swinging the stern into the sea. We rowed with some vigour in the resulting slick to get under the falls and in rough weather storm pennants we’re used.
As soon as the boat was hooked on the boat was hoisted by hand with each fall being hoisted individually.
When clear of the water the boat was levelled up, the falls were married and the hoisting completed.
This was done by day and by night, we did plane guard on the carrier at night with something refined from the 19th century.
May I ask does the control wire have a weight attached to the handle? If you are having issues with it not spooling out correctly, a little more weight on the end may alleviate that. Also, if the wire is twisting as it comes off the drum, you may want to check the lay or try using a different type of wire that is neutral.
Just some suggestions from reading through your issues.
