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Mr.Rude
09-08-2008, 09:53 PM
I have a safety question... If these boats are suspect to blow overs, (having never piloted one, I am not saying that they are) why do the not have an aileron on the leading edge that can be manipulated suck as an unlimited hydroplane? Obviously not enough downforce to rick a stuff, but something that can pitch a few degrees to "settle" a nose up or overtrim situation.

StratosVT
09-08-2008, 10:27 PM
Don't think the nose is the issue. Tail end is the issue when it starts trapping air. Once that happens, it's too late and don't think trimming the nose would help. jmo

Fish
09-09-2008, 06:48 AM
I am not aware of either being suspect to blow over. The STV runs very flat which IMHO further reduces the chance of blow over and the Q-shot runs pretty flat af well. There have been a few that have gone over, but considering the number of them out there and the varying levels of expereince running 100+mph boats, I would say that both are among the most forgiving high performance boats available.

Having said that, any nucklehead can blow anything over, and freak things like gusts, freak waves, mechanical failures...etc can happen even to the most expereinced, and nothing will replace seat time and familiarity with your ride. He live on the edge and sometimes you fall on the other side of it. Additionally, safety equipment should be standard operating procedure on any hi-po boat.

as for the aileron, I remember back in 1972-73 when my dad first tested this. Most boats were squqare across the front not pickleforks. Tom Huber, the guy who put my dad's molonari back together every time he blew over decided to build his own boat that he felt would be lighter and faster than the molonari (created the Hubercotti). He had the same thoughts as you in his firat design; why not assist the angle of attach by cutting the squared off front and making it adjustable on the fly like an airplane wing.

The results were way to radical and unpredictable using the adjustable aeleron as opposed to using the trim to lift the bow . He took the wing out and they tried it (assuming they would not be able to get enough lift) and it was fast as hell with the pickle fork no wing configuration. They left it like that and the boat more than proved it self against the older squared off front technology not only with my dad, but Bert Serra, Homer Green and a few others who bought the huber cotti's.

imq707s
09-09-2008, 07:00 AM
.......if a driver can't manipulate the trim correctly on the motor to keep the nose down......what makes you think the same drive will be able to control a nose mounted wing to hold the nose down. :confused:

150aintenuff
09-09-2008, 11:05 PM
if an STV can go 151.3 and not blow over why would anyone need a aleron to keep them from not blowing over...

WILDMAN
09-09-2008, 11:22 PM
Most of the blowovers are usually from hitting a wave or wind gust and getting the nose a bit too high, or just overtrimming.

6Killer
09-09-2008, 11:41 PM
I seen them all blow over at one time or another, STV's, Jaguar's, Allison's, Q-Shots, Triad's...you name it, it is always like this.....light + fast = danger. You buy the ticket, you take the ride. Only fast boat I have never seen or herd of going over is a Quartermaster.

STV_Keith
09-10-2008, 12:17 AM
What's the fastest Jaguar, Ally, Q-shot you've heard of? I know Dixon is the man in the STV's at 151. Any others even been close?

rpm racing
09-10-2008, 08:26 AM
OK, whatever, Nick.

Easy for you to say, you've never driven one close to that fast. It's not just a "stab it and hold on" situation. As the boat creeps up on those extreme speeds, it needs more and more negative trim and stern lift to keep it balanced as the aerodynamic lift forces increase.

Some other boats are just plain dangerous at any speed over 100.

Pyro...its actually the other way around. The STV will start to push down to the water harder than the lift it creates. Depending on set up and the balance point of the boat it will "roll over" at any where from 105 to 112 (thats what mine have done) with no trim input at all. The front drops and the boat takes a VERY flat set and starts to haul, as your speed goes over 120 you need to CAREFULLY input trim back into the motor to hold the hull up from skidding on the water because it is running so flat and the deck lid is creating so much down force.

Driving an STV or anything for that matter on the water over 125+ can't be explained with words about how it is done. You have to "feel" it and it is not even close to a point and stab situation, it takes a lot of thought to hit the "UP" button when you are going faster than you have ever gone before and it takes even more thought about lifting off the gas when you have had enough of the stupid situation you have put yourself into it.

But damn is it a rush.

screwedbayou
09-10-2008, 11:29 AM
Pyro...its actually the other way around. The STV will start to push down to the water harder than the lift it creates. Depending on set up and the balance point of the boat it will "roll over" at any where from 105 to 112 (thats what mine have done) with no trim input at all. The front drops and the boat takes a VERY flat set and starts to haul, as your speed goes over 120 you need to CAREFULLY input trim back into the motor to hold the hull up from skidding on the water because it is running so flat and the deck lid is creating so much down force.

Driving an STV or anything for that matter on the water over 125+ can't be explained with words about how it is done. You have to "feel" it and it is not even close to a point and stab situation, it takes a lot of thought to hit the "UP" button when you are going faster than you have ever gone before and it takes even more thought about lifting off the gas when you have had enough of the stupid situation you have put yourself into it.

But damn is it a rush.



well said:thumbsup:

pyro
09-10-2008, 01:21 PM
Yeah, you busted me. I don't know any more about driving an STV than Nick does, I just wanted to call him out for trying to be an expert. :D

I'm familiar with the STV deck design and the progressive downforce effect. Mirages and some others lack this level of deck downforce, so they tend to lift easier when they really get moving.

Regardless, it takes a LOT more than just a heavy foot to make a single outboard do 140+...

patchesII
09-10-2008, 05:19 PM
:D
it takes even more thought about lifting off the gas when you have had enough of the stupid situation you have put yourself into it.

thats funny but i kinda know what he's talking about

jay1
09-10-2008, 07:10 PM
I remember somthing on tv a long time ago...weather it was "thats incredable" "real people"... not sure ......but they were testing a boat with a wing between the sponsons...they did a few runs discribing the effect durring each run and then they flipped it....i think it was even a woman driver.....

Mr.Rude
09-10-2008, 07:32 PM
.......if a driver can't manipulate the trim correctly on the motor to keep the nose down......what makes you think the same drive will be able to control a nose mounted wing to hold the nose down. :confused:

:iagree:CASE CLOSED!

STVRacing
09-10-2008, 09:36 PM
Pyro, I have to disagree with you on the fact of a Mirage getting more lift. Maybe on some but my River Racer has a tendency to drop the bow at anything over 104. This hull is completely stock the way Brad built it in '88. After speaking with him a few years back it was noted that my Mirage has a different bottom then the Jaguar and the Polecat which Im sure has alot to do with the way it runs over 104. When Brad and I spoke he noted on how the Polecat was pretty much prone to blowovers when you would get over 100. So he changed up the bottom a bit to compensate for that action. Ill try to get some pics of my Mirage bottom so it can be compared with the Jaguar and Polecat bottom.

stvhelm
09-10-2008, 09:55 PM
and it takes even more thought about lifting off the gas when you have had enough of the stupid situation you have put yourself into it.

But damn is it a rush.

You got that right:D

dez nuts
09-15-2008, 06:49 PM
Out of all the speed boats i have ran in my life i would say by far the stv is the safest hull to go real fast in. It is a completely different feeling when you get up into the high 120;s and into the 130;s especially with a big gearcase 120 feels very slow to me after years of running my stv 130 feels alot faster but beleive it or not when you get into the mid 130;s it feels even lighter i have been told that the speedmaster feels really good and alot safer on these boats i am sure it would make a difference just never tried it for myself i know they are alot faster with the same motor i have heard up to 10mph maybe more wish i could have tried one i have seen alot more blowovers in marige;s than i have stv;s they seam to fly alot higher than the stv does we did have a 96 collins built marige jaguer down here that ran 127 mph thats the fastest i have sean in one of those or heard of maybe not but that boat did run alot flater than most the mariges that i see maybe because we ran a hyd jackplate on it and once you wind it out you keep raiseing the jack till you lose water presure than one tap down and the boat is real flat and fast but you have to drop the motor as you slow down or it will get hot. Just my thought but i do think the stv is the fastest hull and the safest also. Dave

Russ
09-16-2008, 09:51 PM
I rather like RPM Racings comments on the previous page. Having gone to 130 once in my STV, I could certainly relate to things he was talking about. I also told myself afterwords that I wasn't going there again. I believe these air entrapment MOD VP hulls are truely good for what they were meant to do originally...go pretty fast and make gut wrenching turns. I don't see these boats as the type of boats to attempt speed records with, although folks like Mike Dixon and others have driven them to some pretty fantastic speeds. Personally, I feel it's extremely dangerous but still interesting to witness until something bad happens. My cut on why they are dangerous for speed runs is that these peticular air entrapment hulls build pressure in the tunnels which increases with speed, and force a tendency to want to lift the bow more and more...this would be an example of negative speed stability. You have to reach for the trim to keep the balancing act in check, and even at that, it's a real fragile at these elevated speeds they are getting to. Not allot of margin for error or some other 'event' suddenly thrown into the balancing act to try and manage to avert disaster. A better hull design for chasing these speeds would be 3 point hydros. Their design provides positive speed stability with speed increases as the air they entrap forces the stern of the boat up instead, and keeps the two sponsons in contact with the water providing additional stability and greater margins to control things by. Anyways, interesting topic...and made me think back to my moment of high 'pucker' factor.

baja200merk
09-24-2008, 12:35 AM
You got that right:D
:iagree::iagree::iagree::iagree::iagree:

KID:leaving:

Denny <><
09-24-2008, 05:26 AM
Good thread, you guys have given good advice and instruction to us guys who are
wanting to go fast. Hope some day i'll be posting of my 120 plus m.p.h. experience's.
I agree it's all a learning experience and having big nads to go along.

YELLOWSS
10-06-2008, 08:44 PM
well said phil!!!!!!!! never been in a stv... but i know what it feels like in a ally at 110, and you better have your A game on!!!!!!!!!!!!!! the times i have been in trouble is rough water... at 110 the time you see a few waves and let out of it you have hit them... i was racing a 509 ci bbc chevy powered daytona sunday and hit some rough water.... hit so hard my alien cowl came loose and went into the drink... luckly my buddy got it just before it went under..LOL they all "can" be dangerous!!!!!!!!!!!!!!!!!

but i live for the thrill!!!!!!!!!!

benski
10-10-2008, 01:25 AM
All things end up at an equilibrium...lift,thrust,drag.. how you balance those things, that is the sweet spot. And the faster one goes, the greater the risk.. we have all figured that out(or will) for our own skill level and boat. It's part of the fun! Good clean stuff!:cheers:

mirage243
10-11-2008, 04:16 PM
Pyro, I have to disagree with you on the fact of a Mirage getting more lift. Maybe on some but my River Racer has a tendency to drop the bow at anything over 104. This hull is completely stock the way Brad built it in '88. After speaking with him a few years back it was noted that my Mirage has a different bottom then the Jaguar and the Polecat which Im sure has alot to do with the way it runs over 104. When Brad and I spoke he noted on how the Polecat was pretty much prone to blowovers when you would get over 100. So he changed up the bottom a bit to compensate for that action. Ill try to get some pics of my Mirage bottom so it can be compared with the Jaguar and Polecat bottom.

I have one of the last two real Polecat's left, and they are not prone to blowover at 100 mph. I've been 113 mph in mine in a 1/4 mile and can prove it (not guessing, on the clocks) and I would say that the threshold for it is 115. To run these numbers you must have lot's of power to push the boat, rather than trying to just trim it real high. The boat doesn't like excessive trim, it actually seems to slow it down. The one problem with the Polecat is that the tunnel's are so shallow that it doesn't release air fast enough when you get offf the throttle, it skates something fierce.

As far as the wing theory goes, anytime you are putting downforce on the boat your slowing it down, the boat is it's own wing. You just have to figure out where the sweetspot is by trim, and then figure out how big your balls are.

Sam Baker
05-16-2009, 09:36 AM
What we need is an accellerometer (i.e. what's in a Nintendo Wii controller or Apple i-Phone) that will control trim as an emergency override if the angle of the boat gets to a certain point. Not that that would eliminate the "Oh $hit, I hit a wake at 90+ MPH and am going to get wet" type of blowovers, but would help keep some from getting too close to that breaking point. Theoretically, it could be used to control trim both up and down.

Racemore
05-18-2009, 11:18 PM
What we need is an accellerometer (i.e. what's in a Nintendo Wii controller or Apple i-Phone) that will control trim as an emergency override if the angle of the boat gets to a certain point. Not that that would eliminate the "Oh $hit, I hit a wake at 90+ MPH and am going to get wet" type of blowovers, but would help keep some from getting too close to that breaking point. Theoretically, it could be used to control trim both up and down.

Well that's no fun Sam. 3 things.The throttle,the trim and the conditions you run in.If you can't work #1 and #2 real good #3 will get you wet. Any tidal waterway can make a hole that can result in a bad day. That's what is fun about offshore. Changes are about constant and always on the edge if you want to win.aaaaannd $hithappens.Hate to think I got wet because my i-phone lost signal.:eek::D

aguywithabucket
07-03-2009, 06:15 PM
hahahahahahaha $h!t i had a good laugh on that one but i have been there wher im flying a boat quick glance down to check fule and speed and trim angle and as soon as i look up ther is some wave im about to hit lucky it was one narly tail dace flowed by a jentle stuff and a sharp 90 yea my ribs where alittle sore from the seat but i wasent hitting the water @ 90

Scott in MN
07-03-2009, 06:58 PM
You just have to figure out where the sweetspot is by trim, and then figure out how big your balls are.

I can relate to that, that's the truth on any fast boat regardless of model!!!!

Ranger976
07-07-2009, 08:01 AM
to blowovers would be an AOI (angle of attack indicator). All the jets I have flown in my career have had one. The AOI gives you a warning of when your approaching an imminent stall. The concept is quite simple, there's an actual weather vane on the outside of the fuselage that measures the angle of attack between the relative wind angle and the angle of incidence( the imaginary line that goes from the front to the rear of the boat in the CENTER of the wing or lift). Sensors would be mounted to measure the amount of pressure in the tunnel area would input a data computer along with the AOI data to alert the driver as he/she nears the critical point of developing lift. However, the boat whatever type it is, would have to be subject to wind tunnel testing to find out where the boat or wing starts to develop lift for determing those parameters. Now having said all this, you'd end up taking an additional hit weight wise of maybe 10-15lbs. But may allow the driver to hit NEW speeds safely without any guess work. It's obvious it can't account for a roug wave or wind gust. But with lot's and lot's of MONEY it can be done and cut down the margin of error or over/under trimming. I'm guessing the cost would be around $90-110,000. Now, who's ready to give me a deposit of 10% to start testing....:D:D:D

Jimboat
07-07-2009, 08:44 AM
Ranger976 - i like the direction of your thinking! The usual cause of a tunnel hull blowing over is that the aerodynamic lift (very significant) increases (for any number of possible reasons) more than the hydrodynamic lift can decrease - and the result is more Lift than weight - ie: flying! This can easily happen when a hull is dynamically balanced with much of the overall Lift coming from aerodynamic lift (from deck surfaces and tunnel roof) and the rest coming from hydrodynamic lift (planing sponsons and/or centerpod). When sponson pads wetted planing surfaces are very small and generating a smaller portion of the total hull lift, the resulting increase in aerodynamic lift is too much to handle.

When the hull is at this dynamically balanced state with high aerodynamic contribution, any increase in angle of attack or inherent velocity (relative velocity) can cause an immediate blowover. This could be a wind gust or small wave hit causing increased lift. Unfortunately, the best control of reaction to these circumstances is still the driver.

[see also "How do tunnel boats fly" article (http://www.aeromarineresearch.com/publications/HB_NovDec_2008.html)]

y2kstang
07-07-2009, 10:04 PM
If you combined the AOI guage and tied it into some kinard wings you may be able to get away with it as the kinard could be on an actuator and generate tremendous downforce on the nose to compensate for the excess lift. Only thing is the wings would also have to react to the boat leveling back out and stop generating downforce in order to keep from driving the nose into the water.

Although I still agree with driver awareness being the most realistic method of blowover prevention.

D.B.S
07-07-2009, 10:36 PM
Don't worry about blowing that STV over, you have to do something really bad for that boat to go over, not that it's heavy, just well setup!

mirage243
07-08-2009, 08:36 AM
Although I still agree with driver awareness being the most realistic method of blowover prevention.

Ding, Ding, Ding..................we have a winner.:thumbsup:

aguywithabucket
07-09-2009, 08:32 AM
yea thats the truth u can rig a boat with all the safty stuff u want but really its all about the driver over pushing the boat and himselph and agree with sompthing that cuts out the power to prevent a blowover can also be undisired efect and turn ur flying boat in to a sub. the morle is.. spend time with ur boat in gusty situations and get a feel for it and what it wants to do in thows situation at lower speeds and then start bringing up ur speeds and see how the the boat reacts untill u fell completly cunfertable with it and what it will do in big or small wind gust and wave situations even a smaller dux dingy has thes reactons too and it took me a cuple times figureing out its pirsonality in less then ideal wether

you dont instantly have big balls u haft to grow them!

stv1991
07-11-2009, 08:08 AM
I can attest to the fact that the STV is an extremely stable, forgiving. and flat running boat. I had a '91 STV Pro-Comp and out of all the performance boats I have ever had it was by far, I repeat, by far the most stable and had that "stuck to the water" feel I have ever had. It really inspired my trust in that hull where as many of my previous & post boats have not. Much more squirrelly than that STV. Some things are just designed right out of either luck, skill, or both and this is one of those hulls. I did eventually "stuff" my STV and destroyed the boat and just about myself as well. However, that had nothing to do with the boat itself. It had to do with my stupidity, speed, and most importantly my excessive alcohol intake. I currently own an '02 Canadian Hydrostream Vegas XT and while it is a fast boat, it certainly is no STV. I will eventually put another STV back in my stable. That thing was amazing. No need for a jackplate and I barely had to play with the trim either. I had friends with other boats with similar HP and they screwed around for a long time with set-up, added HP, props, etc and never could match what that STV hull could do. With speed comes danger, I pushed it too far and experienced how hard a hull like that can bite once things go wrong. I still have pieces of the hull hanging in my garage to remind me of this...

y2kstang
07-13-2009, 06:50 PM
My STV is very flat running as well. It is the Mod VP. Funny thing about it is the stern lift I get when it packs air feels spooky. It almost feels like the sponsons are going to go submarine on me and that is with about 3-4 degrees of trim. Hard to bring myself to trim it down when it does it but it definitely performs better when I do.

aguywithabucket
07-14-2009, 03:12 PM
all this talk about stv's and how well they handle just makes me want one even more! funny how the wife dusent thow lol

y2kstang
07-14-2009, 08:47 PM
all this talk about stv's and how well they handle just makes me want one even more! funny how the wife dusent thow lol

Two words for that arguement "Euro Ski" of course that must be followed by "Honey, it is a skit boat, think of the fun we can have skiing and hydro-sliding around the lake" Of course you know that means with her you put in a throttle stop and never exceed 50mph. But when she isn't in the boat throttle stop removed and the fun begins. The throttle stop is for the utter lack of self control I have often been seen to have in the past. Something about the wife screaming in terror is just funny too me but the beating that ensues after said event of terror is....... welll....... not so funny. To be only 4'11" and 100lbs she sure can punch like Mike Tyson.

stv1991
07-18-2009, 08:27 PM
Just got off the water with my Vegas XT. Again, it's nice boat but certainly no STV.

Robb

gearcase
07-21-2009, 12:13 AM
Intresting post. My stv sponson walks when i get out of the throttle. But with the power down it feels great, on a string nice set flat running additude.@ 8000 rpm 14.5X26 BBlades et 3 blade sportmaster 1:87 gears. Maybe a little more trim? Settle down better? it is a 2000 EURO i know this is not the big mph ###s but what u think.

Jimboat
07-21-2009, 07:01 AM
Sounds pretty normal to me. The STV is a very well balanced boat as designed and built. At high speeds, any "change" to the operating conditions - including just backing out of throttle a bit - will slightly disturb the dynamic balance, and require a bit of compensation to return to stability.

gearcase
07-22-2009, 12:35 AM
Ok thanks.

dbug10
09-03-2011, 11:25 PM
Air entrapment hull + to much trim button = BAD DAY !

F14
02-03-2012, 02:28 AM
"I can attest to the fact that the STV is an extremely stable, forgiving. and flat running boat. No need for a jackplate and I barely had to play with the trim either"

You hit it right on the head. Zero - 110, 115 MPH (with a little 260hp), barely 3-4 degrees of trim change. Not sure why some guys run the jack plates. Maybe they want another couple MPH out of her but its way more stress on the transom. No need to mess with it for most of us, keep it simple. Enough other stuff to worry about at those speeds. It has to be the easiest boat to drive at speed. More stable that my Mirage was. Guys if you have not driven one, I highly suggest it. Bang for the buck? cant be beat IMHO.
http://img41.imageshack.us/img41/1000/dscn0230j.jpg (http://imageshack.us/photo/my-images/41/dscn0230j.jpg/)

F14
02-03-2012, 02:35 AM
Intresting post. My stv sponson walks when i get out of the throttle. But with the power down it feels great, on a string nice set flat running additude.@ 8000 rpm 14.5X26 BBlades et 3 blade sportmaster 1:87 gears. Maybe a little more trim? Settle down better? it is a 2000 EURO i know this is not the big mph ###s but what u think.

What motor you running? What speeds are you seeing? That 26 seems a bit light for any big speed.

STV_Keith
02-04-2012, 04:53 AM
F14, is that Wakkers old boat...came out of the Parker, AZ Moovalya keys?

And I run a jack plate for a few reasons:
- to trim the motor way up at the sandbar
- adjustment for playing with top speed vs carrying weight (4 people + cooler vs. just me)
- setback adds bowlift
- setback adds clearance to air deflector

F14
02-04-2012, 12:08 PM
I am not sure if was his old boat? I just picked it up from a guy in So Cal. I have not been able to find out much if its history, but I know it did have a owner or two in AZ. Heres another pic, maybe you can recognize it. Only one I have seen in this color configuration. BTW, you get 4 in your RIver Rocket? They must be some small people. :-)

http://i40.tinypic.com/ay2cfb.jpg

STV_Keith
02-06-2012, 02:46 PM
Yep, Wakkers old boat. You can find Wakker on the River Daves Place forums.

keane
02-06-2012, 03:06 PM
I like the color scheme, it makes it look longer than it really is.

F14
02-06-2012, 07:02 PM
I like the color scheme, it makes it look longer than it really is.I agree with you. I am going to black out a windshield looking area which should improve the look as well.

dbug10
02-06-2012, 09:58 PM
What do you have your mooring lines tied too on the boat ?

F14
02-07-2012, 01:23 AM
What do you have your mooring lines tied too on the boat ?suction cup handles make great temporary cleats. The are no cleats on these boats.

2old2moto
10-17-2012, 10:32 AM
sweet boat ,, i have a 18ft aerodyne pickle and it is more scary when you let off the gas than when you haulin a!!
I am not sure if was his old boat? I just picked it up from a guy in So Cal. I have not been able to find out much if its history, but I know it did have a owner or two in AZ. Heres another pic, maybe you can recognize it. Only one I have seen in this color configuration. BTW, you get 4 in your RIver Rocket? They must be some small people. :-)

http://i40.tinypic.com/ay2cfb.jpg