Anbother vote for the killcord

Rappey

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Do propeller cages cause much in the way of drag
Yes. Even the trim tab/anode causes drag.
I had a 14ft catamaran speed boat and put on a 90hp 2 stroke. Set the engine height as a long shaft and got 30 knts but it didnt feel right as could fell it accelerate over waves but then it felt like i was pulling a sea anchor. Raised the engine 5" to match a short shaft. Straight up to 45 knts.
Im still astounded how 5 " of shaft makes such a huge difference.
 

Snowgoose-1

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Report forwarded via Cargreen YC says emergency response and medical assistance needed. Not good at all
Interesting how yachts and power boats developed with automatic "cruise control" as standard unlike cars and motorcycles . One suspects that trains still have a dead man's handle .

Thoughts are with the family
 

westernman

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Just wondering.
Do propeller cages cause much in the way of drag ?
They are often used on tugs where apparently the increased grip on the water is very useful for low speed manoevers.

And of course of turbo fan engines like on your average Ryan Air Boeing 737 Max.

A high bypass turbo fan is basically a turbo prop engine with a multibladed prop surrounded by an enclosure. And the blade pitch cannot be varied on your B737, where as it can be on almost all turbo prop aircraft.

High bypass turbo fan plane engines are all about fuel efficiency.
 

ylop

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I’m always surprised how few yachtsmen (and women) seem to use the kill cord on their tender. In my experience powerboaters are much more likely to use it - although forgetting, bad habits like not using when starting etc. are all quite possible even in the normally diligent (which is why laws are probably pointless).
 

KevinV

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I assume it’s because they assume a 2HP blender would do less damage than a 30HP blender. The more videos like this shared the better as it really makes the point.
When I've forgotten the kill cord it's been because I hold the engine with my left hand and pull the cord with my right, then use my right for the throttle. This means you can't have the kill cord round your right wrist when starting the engine - and opens up the chance to forget.

Bigger engines will have electric start, so there's no reason to start the engine without the kill cord. I can still envisage it being taken off for docking/undocking when you need to move around handling lines.
 
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lustyd

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I can still envisage it being taken off for docking/undocking when you need to move around handling lines
If you leave the helm take the kill cord with you no ifs no buts just kill the blender before someone gets killed. If you’re worried your engine won’t restart quickly you should do maintenance instead of boating.
 

Rappey

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If you leave the helm take the kill cord with you no ifs no 😬
Taking the kill cord every time is a bit extreme. No way to untie or tie up while wearing the kill cord but that is also the time the throttle can get leant on accidently or a rope snags it.

I see some large centre consol boats dont appear to have kill cords (must be hard wearing 6 though) so at what point does one need or not need one ?
 

ylop

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I assume it’s because they assume a 2HP blender would do less damage than a 30HP blender. The more videos like this shared the better as it really makes the point.
You'll still lose the fight - even with a honda 2hp and a plastic prop there's no way even at tickover I'd put my body part anywhere near it! I think its partly what you say - even though falling overboard on a tender must be more likely that a bigger boat, but also a large dose of "yachtsman complacency" of I've always done it this way. Possibly mixed with "and i'll invent an excuse why I can't do it any other way".
When I've forgotten the kill cord it's been because I hold the engine with my left hand and pull the cord with my right, then use my right for the throttle. This means you can't have the kill cord round your right wrist when starting the engine - and opens up the chance to forget.
Put it on your left wrist, or your leg, or your bouyancy aid/lifejacket. I agree some seem to have been positioned as an afterthought by someone who never started an oboard whilst in a dinghy, but I don't think I've seen any that are impossible. If you want to get in a good habbit - keep it on YOU all the time then to start the engine you need to connect that end (this will also mean your engine is the least convenient to nick as everyone else left theirs dangling).
Bigger engines will have electric start, so there's no reason to start the engine without the kill cord. I can still envisage it being taken off for docking/undocking when you need to move around handling lines.
Its almost always possible to find ways to work without leaving the console.
Taking the kill cord every time is a bit extreme. No way to untie or tie up while wearing the kill cord but that is also the time the throttle can get leant on accidently or a rope snags it.
Which is exactly why its not really extreme. There MAY be particular weird scenarios in an unfamiliar harbour with odd winds and currents where you find the best compromise is to leave the helm - but any powerboat instructor will be able to show you ways to manage it perfectly safely in 99% of scenarios.
I see some large centre consol boats dont appear to have kill cords (must be hard wearing 6 though) so at what point does one need or not need one ?
Multi engine boats have a shared KC between all engines. There will come a point where falling overboard from the helm seat becomes very unlikely.
 
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