Bijan999

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Just curious..

What are some of the fastest jets today and what top speeds are they producing?

How do the turbines compare to the tradional ducted fans in producing fastest top speeds?

Back in the day I remember the BV Viper was running in the neighborhood of 240 mph. Do they still make this kit?

Thanks,
Bijan

grbaker

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Since the AMA bans speed contests with turbines, you don't hear as much about which jet is the fastest anymore.

The big difference is that ducted fan speeds were taken after leveling off from a steep dive. And they were reaching the 200-240mph range. Now you have guys that run speed limiters set so that the turbine powered model doesn't exceed 200mph in level flight. I'm guessing that there are quite a few turbine powered jets out there today that will exceed the Viper's speeds.

JET FX

Fastest production model I have seen would be the JMP Firebird, I have no idea what the top speed reached has been? 300mph??? Ask Tom Cook....

Cheers-

vetagator

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BVM Bandit Baby!!!! Bar none.

skyhawknut

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Take a look at this site and check out the video at the bottom!!!!maybe some of our German friends can translate for us. But 571 kmh = 355 miles per hour or Mach .5!!!! All I can say is Holy ****. What kind of servos hold up to this and how does he see this thing????? watch when the camera man loses sight of the aircraft and focuses on the pilot, if you blink you will miss the a/c streaking by. If this isn't a record I don't know what is. BVM eat your heart out!!

skyhawknut

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Sorry here is the link: www.hessenbruch.de/niels/

Johng

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Yep, we've seen this before - started a reasonably long thread including people talking out of their behinds about how the GPS unit couldn't be trusted as accurate, etc. People taking pot shots about how it isn't true, without having a valid reason for saying so. Prepare for more of the same. Looks entirely plausible to me - FWIW.

LGM Graphix

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The Starjet and Exocet from Aviation Design are supposed to be incredibly fast, particularily the Starjet, looking at it shows why

raiki

I think the Australian record was set by Peter Agnew with an UltraViper at 235mph in Adelaide during the Jet Action 2000 show (I have been to a few but I think this was the year).

I believe it was BVM91 powered.

Since then haven't seen many speed contests, more try and maintain a speed which is generally set in the 120-150mph range (last one I saw was 140mph).

Blueskies21

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Raiki

Quite a few guys have surpassed 235 mph with a viper.BV himself hit 254 back in the early 90's.A couple others have hit high 240's & low 250's respectivefully ..I just got a RTF Viper in a trade last week.We will see how fast & how close she comes next weekend


There is no wonder vipers are so ballistic ,very very streamlined and very light.Mines weighs 10.2 lbs with fuel..I have heard of many vipers (being witnessed) as keeping up with turbine powered jets.They simply to this day are the fastest DF jet


Steve

Minch

The fastest jet that I have seen in the UK is a BVM Bandit powered by an AMT olympus (owned by David Cadman and flown by Steve Elias) In 1999 they tried for the world speed record, I believe their fastest recorded speed was something like 270mph averaging out over 2 runs at about 255mph but I believe they have been faster. I believe they recorded a speed in the 290mph bracket with an on board GPS. I don't know how accurate they are but the aircraft was seriously fast, impossible for me to video anyway.

hornet driver

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a friend of mine has a starfire with a p-120 in it...........and it hauls butt............now with a 160 in it ..whew....

raiki

Blueskies. I get my Viper in about 4 weeks. I have a near new BVM 91R, pressure pipe and Viojett to go in it.

This will be the first jet I have flown. All I can say is 'Thank god for throttles'. hehehe

After a few weeks of 'getting to know it' I'll try to set some records.

Blueskies21

My Feedback: (34)

ok guys lets compare"apples to oranges" here.We all know that 280+ is not much of a feat for a turbine jet this day & time esp. something like a curvy bandit ,razor or starfire.You strap a 26 lb turbine in a 20 lb airframe(namely 1 of the jets mentioned above) & she can gonna hit 300 mph-thats an scientific anominy.I was talking DF power here.You gotta admit that 250+ with a df is a major accomplishment and one that not too many fans can hold their own too.there is very few DF jets around that can blow thru the speed traps at 200 level which doesnt seem to be much of a chore for a viper.I know there are other DF jets out there that can hit these zones as well such as a spectre,aggressor and a interceptor is real close as well


Steve

Vmax

Hi everybody.
Here is the thread mentioned above. Take your time to read and understand it.
If you don´t have enough time to read then read at least post #26 very carefully. These are three planes with the same design.
But different engines.
It was not just one plane built to get the speed. This is more of a process. Each plane was a modified version of the previous plane.
Have fun.

Niels


this is the link to it: http://rcuniverse.com/showthread.php...ighlight=niels

LGM Graphix

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I'll never live that 287mph wonder mistake down will I LOL!!!!
It was admittedly a wrong reading FWIW :stupid:

John Palmer

The guiness book of records has Dave Cadman and Steve Elias as world speed record holders about 3 years ago, with a BVM Bandit and an Olympus I believe. the speed was around 268mph if I recall it properly. I was on the speed gun and can vouch for the speed. The plane hits the drag barrier at around 250 and after that you can double the power but drag squares so you ain't going to go much faster with that design. However the jet efflux is around 700 mph and the right design could achieve 400 to 500 mph. Don't know if that is the direction we want to go in, but possible.

gtmaxx

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Here's the current Official Speed Record:

Click the link below and when the site loads, hit the speed record icon at the left of the screen - you can read it all from there.

http://www.amtjets.com/

Vmax

there are no official speed records set by a jet.
there are two types of speed records!

number one is a current FAI speed record. it is around 343km/h(209mph).

this is the FAI link: http://records.fai.org/models/history.asp?id=4260


number two is the current speed record in the guiness book.
it is around 395 km/h(240mph). these numbers are shown in the guiness book 2003! go to a book store. take a look at it.

everybody here in this forum knows that model jets are able to fly much faster. but these numbes are official.
the records are set with with piston engines.

Niels

erazz

Wow, that looks NEAT!

I have one gripe about the color scheme. You wrote (in the other thread) that pink and green offer the best visability. I'm no expert but here are a couple of things to think about:

1) The most visible color to the human eye is yellow. Basically the reaction of the eye is most pronounced in that wavelength.

2) Our retinas include elements for sensing color and elements for sensing light levels (B&W). We have more of the B&W elements and they are smaller, meaning we see sharper in B&W.

What this means in HiVis model terms: To get the best visability use colors that have opposite gray scale values. Also use some different shape to differentiate top to bottom.

I would use a black and yellow scheme with lenghtwize strips on top and maybe large triangles on the bottom. With yellow leding edges (much more visible when coming in for a landing).

My feeling is that neon colors tend to be 'fuzzy' over a long distance.

Notwithstanding, I think that flying a r/c plane at those speeds (anything above 250mph) is totaly fantastic!


p.s. I have a private pilot's certificate and from my experience with GPS they are right both on speed and on position. I do, however, think that there could be 'spikes' of speed which in turn would be recorded as max speeds. Although since you are getting some rather consistent results I guess that isn't the case.

Vmax

Hi erazz,

imagine a yellow plane below a bright cloud layer.
the contrast betwenn yello and the white cloud is not that much of a difference. the pink colour gives you more of a contrast. don´t just think about the colour yellow. yellow itself is highly visible. no doubts. but think of the combination white and yellow.
yellow in front of a dark blue sky is excellent. but not with white in the background. same goes to black. imagine the black plane in front of a dark blue sky. hard to see. now imagine neon green in front of dark blue sky. it is esier to see.
play the game with different coulour combinations.

just my two cents

Niels

erazz

Hi Niels,

Please reread the first part of what I wrote. We see contrast better than color.

Yes, a yellow airplane in front of a white cloud won't be seen very well. Mostly because both colors are bright. The pink you have is actually not that bright and may very well help you see better.

I know this is hard to grasp at first but when we look at a plane with a 1 meter span at 100 m. What we see is mostly black and white. Our brain is 'wired' to fill in the colors (either from the little we see or from memory).


One more point. The yellow/black scheme would help differentiate top to bottom (good for fun fly and pattern). Now that I think of it, you need something to help you see the airplane against the sky.

The sky is actually quite bright. Even the deep blue variety. Basically any dark color would do the trick. I still would have bright leading edges to help on landings though.

There's a fantastic article from an eye doctor on Model Airplane News about this subject in '91 or '92. It's worth finding and reading (if you have a library that has MAN).

Blue Skyy

My Feedback: (3)

So is the 200mph max speed a myth or is it reality? Seems to me very few turbine A/C follow the rule. Not that I blame the pilots. Watching turbine powered jets go round the field at a slow pace is kinda like watching Indy cars under the yellow flag.

So it's a rule, are there any repercussions like losing your wavier or anything if a pilot exceeds the ruling?

Blue Skyy

Gordon Mc

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It only applies if you are using a speed limiter. If you use the thrust-to-weight limit instead of the speed limit, then the 200 mph does not apply.

Gordon

mr_matt

My Feedback: (10)

OK this is an area that even many CDs get confused about....

There is no (unilateral) 200 MPH speed limit for turbines! This "limit"only applies in specific cases.

Here is the rules from "SAFETY REGULATIONS FOR FIXED/ROTARY WING MODEL AIRCRAFT GAS TURBINES" (AMA document number 513)

Rule Number 2.) Individual engine thrust shall not exceed 35 lbs. Single and/or multiple installations are allowed.
For fixed wing aircraft: The max. installed static Thrust to Weight ratio shall be .9 (dry) unless a speed limiter is used. The limiter will be set to the aircraft manufacturer’s recommended limit or lower. If none available set at 170 mph. The upper limit for all models (that require the use of a speed limiter) shall not exceed 200 mph. Speed limiters shall be accepted by the AMA.


So the "limit" applies IF AND ONLY IF the INSTALLED (key word) thrust to weight ratio (dry) of the model exceeds .9 to 1. So if the INSTALLED thrust to weight is .9 or less, there is no need for a speed limiter and therefore there is no speed "limit".

If and only if a speed limiter is required is there a speed limit imposed. The limit is 200 mph ONLY IF the model manufacturer has rated the model to 200 or more, if their rating is 100 mph it has to be 100 mph! With no manufacturer rating the limit is 170.

Some of you guys might be surprised to check with manufacturers to get the "official" speed rating for their designs!! If someone makes these phone calls I think some of these designs are going to need to slow WAY down (or drop their RPM) at AMA events!!