J
james simpson
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Fe saw's in Legg lake CA. New record 102.9 official NAMBA two way pass Avg. 8) 
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james simpson
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Grimracer
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Wow 100 that is moving..
Now for what i really think.. I think that Electric boats are cool. Tons of fun, and a challenge to tune. However if the big guys think that the LA SAWs are all that guess again. The event is limited to 25 people. This allows the big dogs time to get as many runs as they need to get the record.
People that i know that planed a years worth of testing were cut off from the event as the 25 person limit was very unexpected. Not saying it wasn’t posted some place, just saying very unexpected.
Its a weekend event and they can only handle 25 people.. What does everybody bring 10 boats or more.. crazy..
I guess that the fur will begin to fly if any of the big dogs read this but that’s OK.. Should be fun..
Never the less 100 is darn quick..
Michael Grimracer Zaborowski
Now for what i really think.. I think that Electric boats are cool. Tons of fun, and a challenge to tune. However if the big guys think that the LA SAWs are all that guess again. The event is limited to 25 people. This allows the big dogs time to get as many runs as they need to get the record.
People that i know that planed a years worth of testing were cut off from the event as the 25 person limit was very unexpected. Not saying it wasn’t posted some place, just saying very unexpected.
Its a weekend event and they can only handle 25 people.. What does everybody bring 10 boats or more.. crazy..
I guess that the fur will begin to fly if any of the big dogs read this but that’s OK.. Should be fun..
Never the less 100 is darn quick..
Michael Grimracer Zaborowski
Slideblues
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Blisterin!!!!!!! But the specs prove what it takes ta do it also:
32 cells
Lerner motor
Joerges custom controller
Mod 1945
Add it all up and ya got 102.95 Avg.
Best one way pass 103.68
I really dont get the limited to 25 thing either??????
The top Guy's from all over the US and Europe all together and have a run off as to who is the fastest, thats seems fair.
Slide 8)
But the specs prove what it takes ta do it also:32 cells
Lerner motor
Joerges custom controller
Mod 1945
Add it all up and ya got 102.95 Avg.
Best one way pass 103.68
I really dont get the limited to 25 thing either??????
The top Guy's from all over the US and Europe all together and have a run off as to who is the fastest, thats seems fair.
Slide 8)
T
TomMoorehouse
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that is pretty cool! but they still have not beat Andy Brown!
when are those slow electric boats going to get up to speed? (joking! ;D).
the gas guys are the slow ones now!
when are those slow electric boats going to get up to speed? (joking! ;D).
the gas guys are the slow ones now!
_laxmasta2039
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wow!!
i was just wodering when that would happen.........im kinda dissapointed that it took 32 cells to do it. it was cool when Dick Crowe made his 87, because it wasn't that many cells, and a really little, comparitively inexpensive rigger. i wish the elec racers would keep trying with the low-budget things instead of getting more and more cells........32 high quality cells is alot of cash!! then a got ta have the huge, super duty brushless[and expensive] motor, along w/ ESC. when you add all that up, the low-budget guys like me are forced to eat wake, no matter how much time/effort we put into the boat :- :-
i was just wodering when that would happen.........im kinda dissapointed that it took 32 cells to do it. it was cool when Dick Crowe made his 87, because it wasn't that many cells, and a really little, comparitively inexpensive rigger. i wish the elec racers would keep trying with the low-budget things instead of getting more and more cells........32 high quality cells is alot of cash!! then a got ta have the huge, super duty brushless[and expensive] motor, along w/ ESC. when you add all that up, the low-budget guys like me are forced to eat wake, no matter how much time/effort we put into the boat :- :-
T
TomMoorehouse
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i agree with that lax! electrics can get expensive fast!
Slideblues
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Big bucks? Yep!!!! But I reccomend this video, its a little dark but you can see just how fast that boat was going, I thought he was gonna run outta water before he got it shut down:
http:// www.rumrunnerracing.com/articles/2002saws/MOV00456.MPG
Slide 8)
http:// www.rumrunnerracing.com/articles/2002saws/MOV00456.MPG
Slide 8)
Grimracer
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Sideblues
I have been reading that some guys did not get much of a chance to run as preping 10 boats was cutting their time short... Geesh
25 guys.. still seams a little werd to me.
When you think about it there is no reasion that a E boats should be slower then a nitro boat. In time FE boats will be MUCH faster then piston power.. I wouuld venture to guess that the 175mph mark will be smashed in under 3 years. Piston boats will be reaching 150 maybe..
Grim
I have been reading that some guys did not get much of a chance to run as preping 10 boats was cutting their time short... Geesh
25 guys.. still seams a little werd to me.
When you think about it there is no reasion that a E boats should be slower then a nitro boat. In time FE boats will be MUCH faster then piston power.. I wouuld venture to guess that the 175mph mark will be smashed in under 3 years. Piston boats will be reaching 150 maybe..
Grim
Slideblues
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Yeah the 25 guys thing I just dont get it, there are other ways ta do things that would seem more fair.
All that is needed is a smaller lighter high discharge cell than currently manufactured and a little more tweeking on the motors and its possible. The electronics research will surpass the hobby market as far as high tech stuff goes.
Slide 8)
Hey how about a small hydrogen fuel cell that uses, Yep ya guessed it H2O
All that is needed is a smaller lighter high discharge cell than currently manufactured and a little more tweeking on the motors and its possible. The electronics research will surpass the hobby market as far as high tech stuff goes.
Slide 8)
Hey how about a small hydrogen fuel cell that uses, Yep ya guessed it H2O
Propjockey
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Be looking for some radical hull designs! At those speeds, AEROdynamics play as large a part as hydrodynamics.
A
Anders
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Hi!!
AEROdynamics will NEVER play as large a part as hydrodynamics!!
Have tested Eagle SG 21 and 80 Riggers in a windtunnel so i know now how mutch the AEROdynamics take compered to the hydrodynamics.
I can just say that bring everything out of the water is the key to run fast.
Anders
AEROdynamics will NEVER play as large a part as hydrodynamics!!
Have tested Eagle SG 21 and 80 Riggers in a windtunnel so i know now how mutch the AEROdynamics take compered to the hydrodynamics.
I can just say that bring everything out of the water is the key to run fast.
Anders
_laxmasta2039
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anders........that's pretty hardcore.
i dont think PJ was really being completely serious though.
joe
i dont think PJ was really being completely serious though.
joe
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Anders,
Sounds interesting, was it a moving ground plane tunnel? Or did you just have the models suspended in free air? What was the results of the tests? Did you try the effects of pitching the hull up?
Ian.
Sounds interesting, was it a moving ground plane tunnel? Or did you just have the models suspended in free air? What was the results of the tests? Did you try the effects of pitching the hull up?
Ian.
Propjockey
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Actually, I was serious. (I had to break out the old college physics books for this one.)
"For a given air density, resistance (drag) is directly porportional to the SQUARE of velocity"
In other words, as the speed of an object doubles, the air resistance against it quadruples.
As you take more surface area (hull) out of the water, the aerodynamic forces against it will increase, and the hydrodynamic forces will decrease. True, you may not notice it as much at 80 or 100 MPH, but what about 150? Or 200 (where drag is now 16 times greater than at 50 MPH)?
As speeds increase, hull aerodynamics WILL play a major role.
Ok, now my head hurts!
"For a given air density, resistance (drag) is directly porportional to the SQUARE of velocity"
In other words, as the speed of an object doubles, the air resistance against it quadruples.
As you take more surface area (hull) out of the water, the aerodynamic forces against it will increase, and the hydrodynamic forces will decrease. True, you may not notice it as much at 80 or 100 MPH, but what about 150? Or 200 (where drag is now 16 times greater than at 50 MPH)?
As speeds increase, hull aerodynamics WILL play a major role.
Ok, now my head hurts!
Tom v.d Brink
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propjocky in a way you are right airodynamics plays a role
but anders is right now i don't need to study the specific boats to know this because you know the formula where you found the airo force beeing a factor of the speed squared?
you can apply that same formula to the water resistance force but this time with a medium that's about 100 times as dense as the air
air beeing 1.2 kg/m^3
water beeing 1000 kg/m^3
so you see the water resistance will also go up with speed just always beeing more important than air resistance.
but offcourse when your going for those speeds all the little things have to fall in place to get it even airo's
Tom v.d Brink
but anders is right now i don't need to study the specific boats to know this because you know the formula where you found the airo force beeing a factor of the speed squared?
you can apply that same formula to the water resistance force but this time with a medium that's about 100 times as dense as the air
air beeing 1.2 kg/m^3
water beeing 1000 kg/m^3
so you see the water resistance will also go up with speed just always beeing more important than air resistance.
but offcourse when your going for those speeds all the little things have to fall in place to get it even airo's
Tom v.d Brink
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I agree that water drag will also rise at the same rate as the aerodynamic drag, and thus the water drag will always be a significant factor. However I think aerodynamic stability is a major factor. At those very high speeds very little would be in the water, just the small turn fin, tips of the prop and rudder, due to ground effect aerodynamics the boat would be floating on air! Thus ensuring the boat is stable aerodynamically would be a lot more important than aerodynamic drag, in my opinion!
Ian.
Ian.
_laxmasta2039
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ian,
i agree that the aerodynamic stability plays a big part. thats probably one reason why hydroplanes have a much bigger tendency to flip if a strong wind blows when they are in full song that say catamarans......but other than that, it seems like hydrodynamics would be more important. water is alot more resistant than air, so wouldnt the dynamics be alot more important?
joe
i agree that the aerodynamic stability plays a big part. thats probably one reason why hydroplanes have a much bigger tendency to flip if a strong wind blows when they are in full song that say catamarans......but other than that, it seems like hydrodynamics would be more important. water is alot more resistant than air, so wouldnt the dynamics be alot more important?
joe
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For sure hydro-dynamic drag is much more important for increasing speed, but if you watch most riggers at high speed the sponsons barely touch the water at all, thus little of the stability is coming from the sponsons on the water. Yawing stability comes from the fin, rudder and prop. Pitch stability is from both the sponsons on the water and the aerodynamics.
When you say hydro's flip in wind gusts more than cats, that depends on the type of hydro. Scale types, and semi-scale designs use a lot of aerodynamic lift, so are more influenced by wind gusts than riggers. But a cat is more likely to blow off in a gust than a rigger at the same speed.
Ian.
When you say hydro's flip in wind gusts more than cats, that depends on the type of hydro. Scale types, and semi-scale designs use a lot of aerodynamic lift, so are more influenced by wind gusts than riggers. But a cat is more likely to blow off in a gust than a rigger at the same speed.
Ian.
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