Question about Safety
 

Could you put some type of device in the tunnel of a cat that when it got so much air under it a flap deployed to slow the air going under the boat down and maybe prevent a rollover kinda like a roof flap on nascar. Maybe also when it deployed it would cut fuel to stop the engines. I figure you could set it up to deploy at a certain angle like 45 degrees.

I would like your opinion if you think this would work or not. and if you think the reduced airflow would stop anything after you are already at that point.

I see what you are saying but would you not want the air to pass through the hull at an angle like that? I have no idea if a flap coming down would do much. A hatch that opened and let the air flow through the hull I guess would aid in the blow over situation. Not that I really know have any experience here but just a thought.

A flap like that would just push the boat higher by forcing the air under the flap.

How boat some type of "wheelie bars" that come off the transom, back and out to the sides?

common sense is a pretty good deterant

That's Good!:grinser010:

I think those are called trim tabs on boats...

No , i'm talking about something that would be deployed once the boat's attitude reaches the point of no return, something that would kick in way after tabs. Smart A$$. we're trying to think outside the box here.:D

You would need A. An airbrake type setup like on NASCARS. When the boat got out of shape (kiting) they would deploy and bring it back down. BUT if the boat was really out of shape they might bring it back to the water sideways or upside down (like some NASCARS that have deployed them.) or B. A wing type set up that would maintain the attitude of the boat and prevent it from kiting in the first place. This would need to be computer controlled like on a plane since it would need to operate independent of driver input. (If the driver was aware of what was about to happen he could back off or trim in to avoid it in the first place)

This is not exactly what your talking about but if I'm not mistaken, Buzzi had on the 4 engine Cesa cat an opening in the tunnel to control something??? It was to either let air out so the boat would ride more level or some type of anti-dive device??? I was never around that boat except for a breif time in AC and just didn't pay it much attention. Maybe someone has a picture, I'll look for what I have? I just recall something different in the tunnel toward the front that I thought he could control?

Joe Gere

What ever happened to life vests with parachutes to pull you safely away from the wreckage and slow you down?

My Dad wrecked at over 100 in the 70's and one of these saved him.

or maybe a hole in the floor where you could just stick your feet out( ala fred flintstone)

I think the answer is maybe. Cats run right below the point of instability. That's why there are so many accidents. If they didn't run there, they wouldn't get the reduction in drag due to lift, and the speed. While you might be able to prevent a blowover, the recovery might be another thing, with the bow submarining. It would take a lot of testing to perfect, and I think you might find it hard to get volunteers.:D

Michael

Most cat crashes I have read about are not from blowing over. They are caused by an uneven launch off a wave/wake that causes one sponson to grab and the boat goes into a spin or barrel roll.

I really have what I feel is a great idea brought on by current events. I know it could work with testing. I just wanted opinions. I have it worked out in much more detail than I have given but think about it. An airplane stops with a little wing and some drum brakes. I am not talking about blowoverers I am talking about getting air and bringing it back to a safe point. I will make calls to get testing done but I know it will work just to what degree I have no idea.

An uneavean launch would end the same way as soon as the boat got so much air about 45 degrees whihc should never happen in normal conditions it would bring back to normal if that was what you wanted well the ending would be stopping.

I already have wind tunnel testing ideas which will never replace real world but if it only saves one life is it worth it.

The current Unlimiteds have tested what you are talking about with a gyro to control a wing and effect attitude. We used it on some RC boats with a rc helicopter gyro and a wing with a rapid response servo. If you study both applications, and test in an rc cat, you would be able to figure out if it made sense for a tunnel in a fullsize cat. PM Steve David and he may be able to send you in the right direction.

I thought about what you are saying about rc boats but lets say it is a quarter scale model it would need wind speed of almost 800mph to equal 200mph of a full size boat.

My thinking is opening it with air only (less parts to fail) but where enough air only gets in at a certain angle I even thought about more than one flap depending on the degree of the boat.

The reason why I think it would work in a cat and not an unlimited is because at running speed the tunnel of a cat is out of the water but the bottom of an unlimited is still completely in the water or just above

One of the folks working on a WSR boat had implemented that exact system. It was using some sort of accelerometer system to control the dump of air under the tunnel. But what they were addressing was managing lift in a very static operation- level flight over glass-smooth water. The systems complexity and processing power would grow in unimaginable complexity when put into a highly dynamic 3-axis environment such as an offshore raceboat.

And, since Warby still holds the record, I suspect their effort didn't pan out.

Development of something like this would cost many many millions of dollars and addresses a problem that really isn't there. Very few boats blow over backwards purely because of wing effect. Most are dynamic events- boats being propelled from their line of travel by unexpected forces.

Most likely, the system would cost as much as or more than even the most expensive boat.

Glassdave nailed it. With all due respect to those that have crashed and to those that have suffered injuries or demise, have you ever noticed that the top guys are rarely if ever in these situations? This is a dangeous sport that requires a high level of skill. I certainly don't possess the skills and experience level to operate one of these monsters at 170+. Few do.

P.S. At the first race the Apache cat was run at, in a post-race interview, Ben Kramer stood on the deck and described exactly the same system being discussed here- a dynamic system used to dump air from the tunnel. I still have the old Betamax tape of the interview- somewhere.

That was 1986

link didn't work ?

its a pics of this boat from the top
http://www.aopc.com.au/media/11-8-08/48.html

looking at this vid http://www.youtube.com/watch?v=h6uNwQe4lRU the amount of time to deploy something is incredibly minimal, once you get past 30 degrees or so you have a kite and nothing is going to stop it. any more angle than that and you not only have a high pressure zone under the boat, but at race speeds you also have created a low pressure zone on top of the boat which will suck the boat over.

I think "if ever" are the ones that got out before anything happened. Unfortuntely, there have been very skilled drivers and crew who after many years have experienced tragedy, whether they are cats from Offshore, Unlimited, or Grand Prix. It is a dangerous sport.

Michael

No doubt- some very skilled people have run out of luck on the competitive circuit. But if you ran the numbers, I think you'd find a definite tilt towards the lesser-skilled.

In that youtube video you see the boat go up a little then come down or bounce and then go over if this would have deployed before the bounce and cut fuel or spark or somehow cut the motors I think it would work. I am not thinking anything high tech I am actually thinking very low tech just like a nascar roof flap it would be like a scoop when opened I am not thinking tunneling air into hull or anything crazy just a flap or mutiple flaps.

Now I do not know much about airplanes but when they put the flaps down on the back of a wing they are very effective in slowing the plane down and decreasing lift so a flap in the tunnel or "wing" I feel would have a similar effect.

Now for the side to side crashes it would not work as well but I feel that usually before a sponson stuffs it is at an angle above normal running which would deploy the tab and cut the motors this would not prevent a stuff but could severly cut the speed at which it happens and with the motors stopped it would not keep pushing through the water

airplane wing flaps increase lift

Just my .02 worth and certainly no disrespect to anybody but.........If you'll take a close look at the history of offshore powerboat racing you'll learn about going fast and safety issues. There's been many great people that lost their lives in cats and v's running alot slower than these high speed poker run boats. One thing I learned was to have a full high tech canopy w/ full time air / 5 way harnesses in any competitive event over 90 mph, and this is still no guarantee for survival in a crash. I was violently ejected at over 80 mph in a turn and was lucky to survive. Like I said no disrespect to anybody and hopefully we can all learn from this tragic accident.

most cats that go over do it in the corners... blow overs are almost a non factor (and the few that do happen usually involve taking water down the tunnel from another boat, and a flap at that point would catch even more water, probably knocking you over faster)

i wouldn't take the throttle away from them either, you'd be surprised what a good one can do with it.

To continue the theoretical exercise, an issue that is just as critical would be the reverse- stuffing. Imagine if you had this very basic venting system that dumped lift. The nose of this 44' cat travelling 140+ mph is now 50-60 fet above the water's surface and no longer suspended. It's going to come down hard if your vent stays open. Now we have a real problem.

The system you propose is theoretically possible, but presents a great challenge. You'll have to employ quite an array of accelerometers feeding into a multi-channel processor that controls your system. Then you have to have enough modeling to create the piece of software that analyzes inputs and operates the controls. It has to analyze what's going on and be right 100% of the time. That's alot to ask.

Exactly Sean ,some bad situations have been avoided by being able to power & throttle on thru:drink:

yeah but first ya gotta have it then ya gotta use it

You don't know much about Unlimiteds...both cats and hydros run with their tunnels supported by ground effect airflow beneath the hulls and negative lift above from the airfoil shape on the deck. The technology you describe has been around for years in various forms on OffshoreCats, outboard tunnels and Unlimiteds, and , at times it has worked. However as previously posted most Offshore cat accidents are barrel rolls, not blowovers. This is even the case in most straightaway accidents, including the one a few weeks ago. The few blowovers that occur are at the really high speeds or from excessive trim angles.

T2x

They hurt as much as help...... Many drivers have been injured or worse when the parachute became intangled in the hull.........

They also created neck injuries when drivers bounced off the unopened parachute package as they left the cockpit, but before the chute deployed. This was greatly compounded when drivers forgot to attach the static line....or didn't bother to.

T2x

Reggie tried something like this on a skater he bought.

I saw it at a race and was checking it out I dont think they ever got it to work..

Not to mention, these have been replaced by capsules on drag boats, with much higher effectiveness the result.

Michael

To add to this, the system would not be preventing instability, but having to recover from it, a much harder task. The NASCAR example does not represent the cat situation, becuase the car is still on the ground, and the reverse flap just prevents the car from going unstable and airborn. Even an airplane can be unrecoverable from some unstable conditions. How many planes have plunged thousands of feet in a spin?

Someday it may be possible to build such a system, but it will take some extremely fast processing, and comprehensive programming for all the conditions that could happen: barrel roll, blowoever, trip and stuff, catching sponson, etc. I would think you would need one flap or wing on each corner of the boat. This would be harder than building an automotive stability control. The car is essentially 2D, and this would be 3D.

Michael

getting back to common sense... it's been a bad summer when racing, poker runs and performance boating are looke at as a whole. this is off the top of my head, but the summer started with an offshore boat slamming into an anchored barge at speed in the dark, several ejections and a roll at the harrison twp race, a recent head on at night, a couple high speed shore hits, 2 different cats flipping killing 3, the leopa ejection.. and thats off the top of my head without looking up anything. fancy gyroscope wings, air dumping venturies, and parachutes arent going to fix the problem. we have pleasure boats out there that are faster than most of the race boats, yet lack the safety features. everyone of these accidents effects not only the person involved, but negatively effects their family, friends, employment, coworkers, everybodie insurance premiums, and the sport as a whole as events are canceled, speedlimits enacted etc. we all like going fast and running hard, but collectively we need to step back for just a second,understand our capabilites and that of our boats and stay within those confines. if not there are cheaper and easier ways to commit suicide. we also need t look out for are brothers.. if you see someone running like an idiot, say something..maybe they are suicdal or maybe they just dont know how to set up their boat or how to drive it... maybe they just got a little carried away, we all get a little carried away at times, but that is the fastest way to actually get carried away to the hospital or morgue. maybe it's just me, but the accidents this summer seem to keep coming one after the other.

Not to minimize the deaths this year in our sport, but statistically speaking, the tragedies of our sport are but a miniscule blip when lumped into overall accidental deaths this year.

Taking our sport alone, about two people a day die in boating accidents. 70% of those deaths are the result of drownings due to no life jacket worn. So about 700 people in a year greatly overshadows the tiny number killed in high-performance boating accidents.

But lets take this a step further. 112 people a day die in traffic accidents. So in a week, cars kill more people than boats do all year. It gets worse- 1/4th of those deaths are young people 21 and under. 40% are alcohol related. So if we raised the driving age to 21 and outlawed alcohol, we'd save more lives in a year than die in boating accidents altogether in almost 30 years. And if we could get people to simply put on life jackets, well, you get the picture.

And accidental deaths are pretty far down the list. Heart disease and cancer get waaaay more people. If you really want to delve into it, the cheeseburger you had for lunch is way worse for you than running 130 mph on a crowded lake- not that you should.

and a good percentage of people who fall off boats, sans lifejackets...fall of the swim platform while taking a leak....