ok the boat is faster with a rider then without ??

[afr]

ole red didnt carry the nose at all with a rider same prop same everything other the cooler is a ft back from where it was and built in to the rear cap maybe 10 lbs in total with drinks

how could this be ?? and why ?

[Speed Jr.]

Was your RPM the same? <Big question! After you dumped your passenger off the boat the same day it was slower? Maybe you had much better air this particular day? Your boat may be more efficient at a lower ride angle (Flatter)? Speedo is off :D Any other factors we dont know about? Downwind, upwind, down current? Maybe the prop has less slip at top end with the extra weight?

[afr]

nope the rpm were less as i cant go as fast by myself i still got to much tunnel lift built into the tunnel trap
does anyone have any ideas on how to get more downforsce from the top or decrease lift from the tunnel roof ??
this is not going to be a easy fix

[XstreamVking]

I haven't seen the bottom of your boat. But maybe a piece added to the fwd portion of the tunnel will give you more lift fwd and less at the stern. How about adding wt to the stern. Move gas tank and batt? Make a vee shape in the tunnel? Just guessin, and throwing out some ideas....

[afr]

I haven't seen the bottom of your boat. But maybe a piece added to the fwd portion of the tunnel will give you more lift fwd and less at the stern. How about adding wt to the stern. Move gas tank and batt? Make a vee shape in the tunnel? Just guessin, and throwing out some ideas....
i got pics of it on here somewhere but if you go to my facebook you can see the bottom
i working with aeromarine now as it is now i just need to kill lift on the front or add downforse
i was thinking going a head with a karnard wing and or side skirts like on the mirage

[rock]

Maybe the extra person solved a balance issue?

Rock

[afr]

Maybe the extra person solved a balance issue?

Rock
yes thats is case i forsure need more weight forward be it air or weight prefer to use the air as weight will or should i say pose to slow you down not speed you up now with all that being the case if i use weight it still migh go over without warning as could be the case with the using a kanard as well if it releases im going over

[afr]

well here is the answer i just built in to much lift and its almost impossible to loose it other then a complete re design

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hi Scott - you don't need more down force, you need less lift. with 13.5inches at leading edge on 15.5ft hull, you have 5 degrees of built-in angle of attack on your lifting aerofoil. So, by my software, you generate sufficient lift to fly your boat with zero sponson angle (zero/flat trim) up until about 70 mph. this is not very efficient for the sponson lift, and so you are probably applying positive trim during this acceleration range, then at higher velocities, you're finding that there is so much aero lift, that you're flying - so need to trim down...perhaps until sponson angle is close to zero again (which means aerofoil is still at 5 degrees!). This is not efficient and your boat knows it. Your hump zone occurs at 55mph and your hull becomes unstable at 75 mph. more weight delays this instability, but it will still be there. You should be able to get this hull to 90mph....but I think your aerofoil angle (5 degrees) is just too much. 2.5 degrees would seem to be plenty.

If you have any questions, call me personally (519-622-3987) or email ([email protected]).

[rock]

ain't this place awesome.

Rock

[afr]

ain't this place awesome.

Rock
yes it is speacialy for a self taught engineer like myself
i still might be able to fix it with a karnard but everthing would be riding on the kanard after 70

[Da Bull]

I`m confused, Is this boat a hydro or a something else. I always understood it to be a hydro that is suppose to plow the sponsons and pop the tail, Not the other way around.

DB

[patchesII]

That's what I thought too Bobby. All BS aside Scott what's the fastest you've been

[afr]

to answer bobby and erik (no bs ) best i remeber its been a while 77.4 by myself top speed this last saturday was 72.4 by myself
and it will pop the tail but only with the added weight i been trying to keep the front down on this thing since i built it during design / construction everyone had me so worried about stuffing /i built in the extra wing angle which is great for rough water and large boat wakes but it just dont have the speed this boat has never been wot with the v6
i think it would be fine with a smaller lighter motor with the same hp

[afr]

and all this time i was limiited to just 3 degrees of negative trim now i moved the pin in a hole i can get like 7 negative now
it all might be just driver error even with the added angle of attack like jim said i should be able to go at least 90

[euro scott]

just bolt a 280 on it and end of story... lol...

[afr]

just bolt a 280 on it and end of story... lol...
its like a 240 hp on there now

[HStream1]

Have you tried stocking the cooler with light Beer instead of Regular Beer? Just a thought?

[euro scott]

Im thinking more like 175 hp, a 280 on most anything sub 800 lbs will run a 100

[That's Right]

Scott were you going faster with the rider? On your boat the bow is going to start coming down at a certain speed and the stern is going to start coming up, maybe you are pushing a little harder with the rider.

[Mr. Demeanor]

What kind of speed difference re you talking about?

[afr]

Scott were you going faster with the rider? On your boat the bow is going to start coming down at a certain speed and the stern is going to start coming up, maybe you are pushing a little harder with the rider.
yes wayne the nose stays down with a rider and the tail pops around 68 only took my rider up to 70.4
so the speed differance is like minimal 5m mph or so but the handeling is there with as apose to without its flying the nose again or still

[That's Right]

yes wayne the nose stays down with a rider and the tail pops around 68 only took my rider up to 70.4
so the speed differance is like minimal 5m mph or so but the handeling is there with as apose to without its flying the nose again or still

Scott, are you worried about the bow not being high enough? I don't understand, that should be a good thing, Kick that mf'r and see if it starts to fly.

[afr]

Scott, are you worried about the bow not being high enough? I don't understand, that should be a good thing, Kick that mf'r and see if it starts to fly.
its is flying already thats the problem or so it feels like to me

[afr]

well i decided ole red will be retired as a speed boat and new red will be coming in the future
i call it a swing and thriple looking for the home run on the next one
theres just to many changes already done to it now plus as it is i need to reduce the lift under the boats sponsons by half thats a major deal to fix im still waiting to talk to one more exspert on what i might be able to do with sponson angles to compesate for the extra lift

[afr]

well no word yet but heres my thoughts on a possible fix

http://www.boatdesign.net/forums/boat-design/back-ole-red-hydro-handeling-issues-s-41147.html#post513757

[Jimboat]

hi scott - i got your message....we've been without power for a few days...seems to be ok now, though...give me a call anytime.

/jim