Speed record of powered aircraft models

Does anybody here have access to a recent Guinness Book of Records? The edition in my (rather poor) local library is of 1989(!), and the
online version of the Guinness book only offers a reduced sample of records (the one sought not being among them). The only speed record of an engine powered aircraft model about which I know in detail is the one by David Cadman`s BVM Bandit with AMT Olympus turbine on 9-11-1999 (254.5mph). And someone on this newsgroup wrote on 11-27-2000 about an Aviation Design Starjet with JPX turbine going 272mph, but giving neither the date on which it happened nor his source. I have not found anything more recent. Can anyone here help me out? Thanks
Peter
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Try the FAI web site. All official records are on the site... if only you can navigate it :)

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I don't think either of those planes meet the FAI requirements for record attemps. That would mean that they are not certified world records.

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Paul McIntosh wrote:

FAI records are made under strictly controlled conditions and they don't show a category for RC reaction engines as they do for CL. However it's quite possible that the speeds mentioned could have been obtained by the usual RC method of climbing almost out of sight then diving straight down which effectively adds the weight of the model to the engine's thrust. Just for the record (hahaha) these are the highest speeds on the FAI site. CL 2.5cc 208mph CL 10cc 214mph CL reaction (pulse jet I'm sure) 246mph RC (piston engine) 213.7mph RC (speed in a closed circuit) 150mph
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I knew there was something I meant to add to my other post. If you want to see (and hear!!) the CL world record at 208mph being made then go to http://www.flyrc.org.uk/ and turn up the volume :)
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Brian wrote:

I was just about to add that myself ! The link to the video is the second item on the left-hand side of the opening page.
Paul says the engine was turning at over 36000rpm. I got an email from someone in Oz who reckoned they'd analysed the video soundtrack and calculated a speed of over 39000rpm. Whichever it is, I doubt many of us have heard a 2-stroke engine running that fast ;-)
--
John P. - who flies on Epsom Downs, UK.
http://www.flyrc.org.uk /
  Click to see the full signature.
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On Wed, 28 Jan 2004 01:30:33 -0000, "John Privett"

Yeehaw! Pretty impressive all the way around.
Thanks for the link.
                    Marty
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Thank you for your kind attempts, guys, but this thread has gotten off the track. Nowhere have I indicated (nor do I have) any interest in FAI records. Besides, they are easily available online (www.fai.org).
Instead, I have specifically asked for the speed record of powered aircraft models (and I should have added: Remote Controlled) as listed in a recent *GUINNESS BOOK OF RECORDS*.
Hope I have made myself clear this time. Does anybody here have access to a recent edition of this book? Thanks very much in advance for your help.
Peter
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I think everyone knew what you wanted but how well does the speed have to be verified? FAI conditions are very strict which eliminates the cowboys who claim to go faster than 200mph with their OS40LA powered Diamond Dusters. What about the glider that NASA dropped from a high altitude balloon and approached Mach1? Or this link http://www.justengines.unseen.org/gbrec.htm to a British RC speed record of almost 184mph where a practise run reached 234mph but the timing equipment was suspect (not to mention that the engine would have had to have suddenly doubled its HP)? I doubt that the Guiness book of records is terribly interested in the methods used to claim a record so long as the measuring equipment is more sophisticated than an egg timer :)
Peter Holm wrote:

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Perfectly clear... Maybe Barnes & Noble? Dr.1 Driver "There's a Hun in the sun!"
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wrote:

The last piston-powered FAI speed record was set in 1971 (!):
N145: Speed : 343.92 km/h
Date of flight: 21/09/1971 Pilot: Vladimir GOUKOUNE (USSR) Co-pilots: Valeri MYAKININE Course/place: Klementyeva (Russia)
Maynard Hill holds the record for closed-course speed:
Sub-class F3A (Aeroplane, piston motor)
N147: Speed in a closed circuit : 241.80 km/h
Date of flight: 26/11/1984 Pilot: Maynard L. HILL (USA) Course/place: Rockville, MD (USA)
Cf. <http://records.fai.org/models/current.asp?id 2>
The FAI seems to have no category for RC jets, as someone mentioned earlier in this thread.
FAI rules for the speed trap:
7.5. SPECIAL RULES FOR SPEED RECORDS IN A STRAIGHT LINE
7.5.1. Base:
For model aircraft of the Free Flight sub-classes, the record is measured over a base of 50 m for model aircraft with elastic type motors and of 100 m for model aircraft with piston type motors.
The course must be flown in both directions within 30 minutes.
For radio controlled model aircraft the base must be 200 m, and it must be traversed in both directions without any intermediate landing.
The altitude of the model aircraft must remain below 35 m and above 5 m during the 100 m entry and 200 m course. These altitudes are measured from the point where the pilot is standing.
The dossier of the record must include a certified measurement of the course and a statement of the methods used to determine altitude and speed.
For radio control speed record attempts the model aircraft must be fitted with a throttle or any other device to stop the motor by radio control.
7.5.2. Timing:
The timing of speed records must be effected by timing instruments approved by the National Airsports Control.
The time is taken as the model aircraft enters and leaves the base. Timekeeping must be effected by two timekeepers equipped with electronic stopwatches recording to at least 1/100 of a second. The difference between the times registered by the two time-keepers must not exceed 0.05 second.
Automatic timing devices are allowed provided the system is properly documented in the dossier and approved by the NAC of the claimant.
For speeds above 300 km/h manual activation of timing devices is not permitted. Only automatic means of timing which eliminate the human error factor are permitted and must be certified accurate within 1/100 of a second.
The mean of the two speeds of the two runs over the timing base gives the record speed.
                    Marty
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(snip)
...and record N145 is in sub-category (F3A) which has become irrelevant for the overall speed record of engine powered radio controlled model aircraft: Piston motors.
Since you guys have been so "helpful", I have invested the time and gasoline to drive to the next university library which has the 91, 01 and 04 editions of the Guinness book. So here is what I found out:
All the 2004 edition mentions about model aircraft is the biggest plastic model collection. In the 2001 edition there is no mention about model aircraft at all. And the 1991 edition (just like in the 89 edition) lists the old record by Goukoune and Myakinine mentioned above by Martin X. So what has happened? The answer I found in the foreword of the 91 edition: "In those activities which are regulated by recognized national or international organizations, these organizations shall be consulted and involved in the ratification of the fact." (translated from the Spanish).
In other words: The FAI has had its fingers in there. What a non-insider would find amazing, is the fact that the FAI has categories of speed records for all sorts of model aircraft exept those who excel in speed: Radio Jets (for common sense, radio controled turbojet engine driven model aircraft should consitute an exclusive sub-class of category F3). The consequence is, that there does not exist an FAI approved overall speed record of engine powered radio controlled model aircraft that would be publishable in the Guinness book. Of course, the Guinness people would not publish any such speed record if it were claimed for a piston engine, pulsejet or ducted fan powered craft, since they know that physics works the same way at the model scale as it does at full scale (some people on this newsgroup actually appear to not know this).
Therefore, the correct answer to my original question which started this thread five days ago would have been: There does no more exist one generally recognized speed record for radio controlled engine powered model aircraft. Neither in the FAI nor in the Guinness Book of Records.
Seems strange that aparently nobody here knew that. Or perhaps you guys just looked for an oportunity to babble about a desperately whining 2-stroke motor tied to a string? To add my 2 cents worth on this subject: I consider control line aircraft models to be the most dangerous ones of all, since these things fly just neck high: They are potential flying guillotines.
Peter
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On 1 Feb 2004 05:39:13 -0800, snipped-for-privacy@infocanarias.com (Peter Holm) wrote:

I'm not sure how the FAI develops new categories.
But one consideration that has not come up yet is their definition of a "model aircraft": it must weigh less than 5 kg in its takeoff configuration.
I have a suspicion that there aren't many 5 kg jets flying right now. They may come some day, and then, I suppose, the FAI will have to create a new category.

I find this sentence obscure.
I don't know what the Guinness people know or don't know about scaling effects (Reynolds numbers, weight, strength, etc.). Some people in this newsgroup are rocket scientists and know their aerodynamics inside out; others, like myself, just dream of being an aeronautics engineer.

OK. If you take away weight and size limits, I'll bet that the US military holds the record for unmanned aerial vehicles (UAVs) or remotely piloted vehicles (RPVs):
"There are some small supersonic targets in the U.S. inventory, and larger, higher-performance vehicles are being developed. The latest USAF target drone is the supersonic BQM-34F. Most Air Force target drones have augmentation devices on board to enhance the radar or infrared (IR) signature so as to simulate a full-size target. As these are unsatisfactory for some aspect angles, new efforts are being directed toward full-scale maneuvering targets. In order to present more realistic targets, maneuverability and variable speed are being designed into even the small subsonic targets." <http://www.airpower.maxwell.af.mil/airchronicles/aureview/1973/sep-oct/kellerstrass.html
If you want to beat the best in the unlimited class, you've probably got to top the D-21, which flew at about Mach 3.3: <http://www.spyflight.co.uk/D21.htm

That's life in newsgroups. ;o)
                    Marty
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snipped-for-privacy@infocanarias.com says...

The problem is where do you draw the line? What constitutes a model, and what constitutes an RPV?
If you look over a Guinness book, what do you see for a world record in say a car or a boat. Largest by weight, length, width, etc. Fastest over such and such a course. There is nothing in there about categories, nearly every class is unlimited. Guinness isn't big on arbitrary categories.
With that thought in mind, Germany added radio control units to fighters and bombers in WW2. A pilot in a chase plane would dive the model into a target. These aircraft obviously flew over 400 mph. Do you allow them in, since they were never under autonomous control? What limitations do you put on the operator. Must he be still, or is he allowed in a chase vehicle? Guinness doesn't like to fool with records that contain arbitrary conditions imposed on contestants, so they leave those to groups like the FAI. The FAI won't fool with an unlimited class record, because there is no point. No civilian would ever be able to beat 50 year old records, let alone what the Air Force is doing today, or even back in the 60's and 70's.+

So, how do you define dangerous? ALL control line models MUST submit to a line pull test, and the lines are thoroughly inspected. UNLESS there is a catastrophic failure of these tested components, there is little chance of anyone getting hurt. Every time you take an RC off, you stand the danger of someone turning on a radio to your channel, and there isn't a darn thing you can do to regain control. And how many points of failure are there in an RC compared to a control line plane? Which is inherently more dangerous? Don't let stats like insurance claims get in the way of your opinion, either. Lastly, neck high means they don't have far to fall, and these models are inherently unstable. They don't go far if something breaks, unless you count after the bounce.
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says...

Does being an amateur constitute an arbitrary category? Aircraft model flying is not the only recreational activity, where the borderline between amateurs and professionals might be getting somewhat blurred. For example, this condition today is already much more advanced in modern amateur astronomy than in model aircraft flying. And just as in model aircraft flying, it has been caused by the availability of advanced technology to the amateur.
The concept of model aircraft flying has in fact always implied that it is done by amateurs. And due to the advent of micro turbines, we now have a new branch of high tech model aircraft flying developing and extending itself. And this new development means, that the definition of the model aircraft pilot has to adapt itself to the new circumstance in such a manner, that the always implied amateur status of the model aircraft pilot has now to be made explicit.
In other words: The amateur status of the aircraft modeler has to become the key element in the definition of his product (the "model aircraft"), in distinction to the UAV or whatever. There are winds of change blowing, and the amateur model aircraft piloting community will not forever be able to shield them off.
And being a recreational amateur occupation, as long as private airplanes do not become as common as private cars, it ought to be self evident that the amateur has to remain on the ground while piloting his aircraft (no chase plane, and it seems almost ridiculous having to mention this).
If this is too arbitrary for the Guinness book, it ought not be too arbitrary for the FAI.

(cut)
ALL control line models MUST submit to a line pull test regardless of where and when they are flown? The only memory I have of seeing a CL model was during my childhood somewhere in the countryside. It was an impressive model of a WWII fighter, and not exactly small (50+cm). In spite of all of my fascination, when it flew I got scared and ducked. Some of the onlookers stood no more than 20ft (6m) from the passing airplane. Nobody of them cared to check the model if it satisfied AMA (or their german equivalent) regulations. Just a personal memory.
Peter
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snipped-for-privacy@infocanarias.com says...
I snipped all that stuff on amateurs. As you pointed out in your other post, there are engines now available to our hobby that can propel models at near supersonic speeds. To try to fly models at those speeds from a fixed point on the ground is ludicrous, and could not be done in a safe manner. Encouraging such activities would only draw unwanted government attention to our hobby. One Sixty minutes style article on the capabilities of the jets in our hobby, coupled with the off-the- shelf auto-pilot systems we can get, combined to give the impression of v-1 wanna-be's, could wreck the hobby as we know it.

http://www.modelaircraft.org/templates/ama/PDF-files/Rulebook/cline1.pdf Scroll down to number six.
The AMA safety code says that every CL plane must meet these competition criteria. See the safety code, and scroll down to Control line. It's number one.
http://www.modelaircraft.org/templates/ama/PDF-files/105.pdf
Failure to do a pull test on your model could void any insurance claims. Few people I know do it every time they fly. Every plane I've built I did a pull test before the first flight, and every few times out, which is what most modelers not competing seem to do. I pull test every new set of lines, and inspect them frequently (when I roll them out, when I pick them up, and any time they are disturbed for any reason).
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There appears to not be a record that satisfies YOUR interpretation of it, but the FAI certainly is recognized and has records listed in all its categories.

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Lighten up - you've jumped on people for not providing you with the precise answer to your question, then criticized them for discussing subtopics that are spawned by that question. It's a newsgroup, man, this is what happens. Perhaps you could simply thank people who may happen to answer your question, and let the rest ramble on on their own topics without insulting them. Keep on at people like you do below and you'll be real lucky to get an answer from anyone.
If you attack one facet of this hobby with disparaging comments, such as criticizing control line aircraft as not really flying (that was another poster), or being "the most dangerous", then people who are advocates of those models or simply those who do not like such comments are going to invest the time to get their point to the contrary across.
My comments for example were in response to someone else's unwarranted and technically inaccurate statement about the C/L FAI speed record flight. My pleasure at watching the video of that model was a direct result of your original question, which prompted someone to offer the link to that particular record being set, and so on. Then I got to thinking about the physics of the flight, and decided to figure out how much of a role the wings play. It's not an answer to your question, but it was an enjoyable diversion that I thought might be of interest to some of those who commented on that flight/video.
My two cents worth - nearly all model airplanes are potentially dangerous, the exception being perhaps light weight rubber or glider models. I've had a hell of a lot more close shaves and scares with R/C models than with control line. I've had idiots land over the pits with .60 size models and felt the downwash from the wings it was so close to my head. I've had idiots not check the strip for bodies, simply set the model down and pin the throttle - towards me as I was retrieving a stalled model (I fell flat to the ground and was missed). I've ducked behind my car to avoid flying debris from a midair between pylon racers. I saw a ducted fan jet tip stall on takeoff and whomp into the ground in the spectator area (at Muncie HQ). The list goes on. Control line scares me a lot less than R/C! With C/L generally you know the model is going to hit in the circle.
Mike D.

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Recently I received the following letter in my mailbox. With the kind permission of the author I am publishing it here without any omissions, but will also take the liberty to comment it. Since the Google editor seems to insist on destroying the habitual alineation of arrows on the left hand side of this page, I will use quotation marks and stipled lines instead.
"Dear Sir,
Thank you for your mail.
8 years ago, at the begining of the RC turbine few customer tried to fly faster and faster. At this time, BVM was the only one to fly very fast with a ducted fan model. As soon as the JPX turbine was born, people wanted to fly faster than BVM. So we develpopped the Starjet, first with a JPX T240, and later with a JPX T260. With 6 kg thrust, it flew at 400 km/h at level flight, without diving (mesured with my plane with military radar in french test center) Some customer flew it fasted in diving. Few radar was used, but I don't remember what type (some were made in UK, some were US). None of them were FAI registered. At this time is was funny to do this as they have a limited thrust (maxi 6 kg thrust) and all the same engine, so same diameter, smae fuel tank, same fuel capacity. So we all have the same limit made by a ratio thrust / drag / fuel capacity" ------------------
When it comes to racing one another, it is the athletic performance of the competitors one wants to compare. For that reason, it is desirable that the competitors compete under about the same conditions (even in formula 1 races). But speed records are in great part also technological triumphs, so an equality of technological circumstances among the competitors (or competing machines) does not make sense here.
------------------ "As soon as AMT developped a new type of engine (AMT Pegasus), cutomer imediatly fit this new engine in old plane : BVM bandit and our Exocet (one was flown by Mark Leavsley). Of course speed was much higher, and I think Mark was the faster one, close to 500 km/h in diving. But it was not so interesting as now there is no limit." --------------------
There always exist limits in everything. And in this case, should there not exist any technological limit, there will at least exist a human limit of flying (and seeing) ability.
------------------ "Now turbine are smaller and smaller. Thrust is higher and higher. So there is no speed limit. We are able to design a plane to fly at 700 or 900km/h without big problem. We already do this for UAV customers. The new limit will not be the thrust or the airframe, but how to see it. If you fit an autopilot, there is no limit. If you use binocular, there is no limit. If you just use your eyes to fly it, either you see it and can can fly faster than an other one, either you loose it and you will crash it. But it is very very dangerous. That's why nobody try it again now.
I hope to have answered to all your questions
Regards
Eric RANTET / Aviation Design president ZI le chenet - 91490 MILLY LA FORET - FRANCE tel : int+ 33 1 64 98 93 93 snipped-for-privacy@wanadoo.fr www.adjets.com" -------------------
It is certainly true that radio jets are starting to touch an upper ceiling in terms of controlability with classical methods of model aircraft flying.If we would disregard the time it takes for acceleration and deceleration with throttle lag, a radio jet flying at a constant 300mph could (theoretically) cross a visibility circle with a radius of - lets say - 1400ft (427m) in 6.36 seconds (at a distance of 1400ft a Starjet has an angular size of 14.25arcmin.(length) x 13.00arcmin.(wingspan). For comparison, the full moon has an angular diameter of 30arcmin.).
But do these three options which you have mentioned above (autopilot, binoculars and naked vision) have to be mutually exclusive, i.e. are they "either or" options? I dont believe so.
Already today radio jet flying has become the high tech option of aircraft model flying. Radio jets do not only have brakes on their wheels, but they have electronic devices (ECUs) interfering in and modulating the commands which the pilot sends to the motor and shutting off the motor in case of a failsafe, some of them have gyroscopes steering the rudder during takeoff, and some of them even have a telemetry system including altimeter and GPS.
So if full scale jets often have to fly with computer assistance, why shouldnt the same thing happen to radio jets? With all of the surplus power supplied by the micro turbine, what reasons would there speak against a few aditional airborne microchips and more sophisticated gyroscopes (sort of an auxiliary autopilot) which could autonomously return the jet towards the radio control in case of being comanded to do so by the pilot or in the case of loss of radio control? Radio jets were never meant to be cheap.
Some people might say it wouldnt be fun to fly a radio jet with an auxiliary autopilot. Some people might prefer to risk busting a model worth various thousands of Dollars every time they try to probe its - or their - limit. But I could imagine that in the future the flying of high tech model aircraft would sometimes be like walking a tightrope - with an electronic safety net strung below. Why should, in the case of radio jets, it forever be obligatory to crash ones aircraft in the case of loss of control? At any rate, I doubt that it will ever be a good idea to fly radio jets within a - lets say - 2 mile (3km) radius of any settlement or major traffic route.
Of course, the attempt to fly a speed record in a straight line with the help of an autopilot has little or no point, so in this case its use should be invalidating the attempt. But this might well be different with the attempt to fly a speed record in a closed circuit as a purely technological endeavour, i.e. as a sort of an "electronic control line" speed record.
But aside from such dreams about a possible future: Radio jets are very expensive, and they require the flying skills of an experienced model aircraft pilot. These factors by themselves should be able to eliminate inept jerks from the ranks of radio jet pilots. And a radio jet which crashes with its turbine shut down by the failsafe routine of an ECU is less of a fire hazard than a model aircraft with piston motor, since kerosene is much less flamable than the fuel of IC engines.
Airplanes, big and small and regardless of their propulsion system, have the propensity to sometimes fall from the sky. So where are the statistics which demonstrate the higher danger, which stems from radio jets? As of right now, all of the flurry around radio jets appears to be based on nothing but (paranoid, I would say) speculations.
It doubtlessly is a very timely idea if, under the new circumstances we are having today, the AMA is trying to guarantee a high degree of proficency among the radio jet pilots it insures. But when the AMA tries to "resolve" the new situation by imposing a 50lb (23kp/220N) combined thrust and 200mph (322km/h) speed limit on radio jets, it appears to me like hanging crucifixes and garlic against the evil spirits of the future. Actually, I believe that this future will come with or without the AMA trying to prevent it. And in the case of a 200mph speed limit, there will just be a lot of wild radio jet flying.
By the way: In Australia they still have speed events on jet meetings. See www.geocities.com/eaussie01au/jetaction.html.
So when I open the JPO homepage (www.jetpilots.org) an see their motto "Focused on the Future" it makes me wonder: What kind of future are these people focusing on, if any? One that is equal to the present? The introduction of micro turbines on the scene less than 10 years ago meant the advent of high tech model aircraft flying. Could it be that this development has already ended up in a dead alley today? The JPO at least appears to be not doing anything to prevent this. Or what has one to think about a double-dealing position paper in which on one hand the speed limit is accepted on the mere grounds of being "inherently safer" than no speed limit, but then on the other hand it is advised against the installation of speed sensors for reasons of them alledgedly being unreliable or even a nuisance? Basically, they also seem to think that the current developments in model aircraft flying can be brought under control by limiting regulations only. Would they be talking differently, if the "auxiliary autopilot" envisioned above would already exist on the market? Or are they perhaps just trying to be politically correct?
Peter Holm
First footnote: As far as I know, all of the contemporary micro turbines still remind of the homemade origin of the KJ-66, with their more cylindrical than annular flame holders of highly non-aerodynamical shape with their flat fronts and their obviously very uneven air influx into the flame holder (straight air path to the outer wall, Z-shaped airpath to the inner wall). But today next to all of the micro turbines are sold ready-to-fly, and are produced in series by means of tools that are more sophisticated than those available to the average homebuilder. Nevertheless, in contrast to the great variety of construction concepts among full scale turbojet engines, all micro turbines are still built in basically the same manner. So I, as a non-engineer, sometimes wonder about what would be the effect of mounting two instead of just one compressor wheel (both on the same axis). That should not increase the diameter of the turbine. And with more pressure one could build a more complex diffuser, which in turn would make possible the construction of a more aerodynamical flame holder with an even air influx from all sides, thus increasing the air throughput through the engine. With increased pressure it would perhaps even be possible to build a smaller combustion chamber. And if there is a higher air throughput and greater pressure in the combustion chamber, why not mount three turbine wheels instead of just one (all on the same axis)? If this should produce a heating problem for the turbines, an airbleed from the compressor for cooling them might increase the maximum diameter of the turbine (if the combustion chamber cant be made smaller with respect to the turbine diameter) .
Now this might be just a dream of a non-engineer, but am I the only one here who would like to see how such an engine would perform if mounted on an adequate airframe?
Second footnote. Micro turbine rotors ought to be good candidates for being the fastest rotating things on earth, with the SimJet 700M going at 3300 revolutions per second (200.000rpm). The only things I know which can rotate as fast are microsecond pulsars (ultradense, superfast rotating stars which are made up entirely of neutrons and are produced by supernovae).
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Peter Holm wrote:

The fastest pulsars are known as millisecond, not microsecond, pulsars. The fastest spin at several hundred rotations per second, well below turbine speeds. Then again, most turbines aren't 10 miles in diameter (a quark star is about 6 miles in diameter and is a compressed neutron star) As for the fastest rotating thing on Earth, I don't know what the current record is but many years ago the Guinness Book of Records (which I'm sure you're familiar with) had a listing for an experiment on producing gravitational waves by spinning a 1mm diam ball at 1 million revs per second...yes, that's 60 million rpm!
Brian Hampton Adelaide, South Oz
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