UFO Helithruster

[birdy]

Coupla points Rick, im thinkn he,s stretchn the effect of that small surface, unless he,s do,n 150kts.For any ground effect benifit from it, youd have to be touchn down at cessna speed.He " believes"??Dont he hava rotor tac?Sure test would be go for a lap as is, then take the wings off n go again.The difference in rrpms will give an accurate calculation of how much lift its producen.It may seem attractive, but wotever the payload/AS gain, itll only be at speed.Dont think that wot you can carry at 70kts is wot you can take off with.

[gyroo]

Re the Arrowcopter,It"s a jazzy space-age intriguing design, but it also tops the scales as the heaviest European gyro by a long shot: the "bare bones" unequipped machine has an empty weight of 342 kg, 80 to 100 kg heavier than its German Autogyro cousins. That"s a comparatively huge difference.Taking a look at the attached picture, you can see that the main-gear-outrigger-come-stub-wings have a pretty decent surface area and I would have no doubt that they"d be a moderately effective lifting surface at high speeds. What they might do, as Rick has suggested, is possibly carry the excess weight of the design so that the rotor at higher speeds behaves like its attached to a gyro 50-100 kg lighter. Of course, the stub wings will be of little help below 40 knots, which is where the fact that this machine is a real heavyweight might jump up and bite the unwary or complacent.Mark R

[birdy]

Hmmm, yeh, they are alot bigger n the ones i was thinkn of.Still, if it did lift even 50 kg off the rotor, itd give it an edge for cruisen at a good speed.Wunder if anyone will do a with n without test.Simple test will tell all.

[MadMuz]

To me it looks like it might be at its most effective (lift) on landing flare and takeoff (in ground effect) and in flight just carry a bit of weight. It is also right under the CofG with tapered ends.... I think that should function well and not cause too many issues.... it will also reduce the drag from the undercarriage legs which can only be good..... far more sensible than a canard or something

[RickE]

I wasn"t aware that the AC was so heavy. I have seen the only one in Oz flying at a few airshows etc but I have only ever seen it being flown one up. There may be a reason for that.I must admit though it is an extremely impressive machine and certainly attracts attention wherever it turns up.I,d have one!

[MadMuz]

I wonder if someone has wings on a gyro that can lift say 100Kg, they can take off with MTOW of 700Kg because in flight, it will only weigh 600Kg (LMAO)I wouldn"t want to be a test pilot for these "bling" machines..... often "far fetched/should work" things don"t.... they just don"t and there is only one way to find out if it works.... well 2 actually 1/ get a test pilot to flog it around to see if it works or not, or 2/

[gyroo]

Hi Rick,342 kg, although heavy, isn"t disastrous. Consider if the PIC weighs 90 kg and the PAX also weighs 90 kg, that"s a combined weight of 180 kg. Add 342 and 180 and you get 522 kg. That leaves room for 78 kg of goodies OR fuel, if one is to stay at or under 600 kg as the wheels leave the ground. ArrowCopter are smart - they publish the gross weight as "...up to 600 kg, according to national rules."What these figures do show, however, is that if 2 seat manufacturers keep their empty weight to between 240 - 280 kg - as most of the European manufacturers say that they do, (other than ArrowCopter), then you can have a really decent, practical and fully legal cross country gyro. Lets pick 260 as a good median empty weight, then chuck in our 2 x 90 kg mature age males = 440 kg. That still leaves a whopping 160 kg for fuel and/or goodies. 1 litre of gasoline weighs .72 kg, so 100 litres weighs 72 kg, so if you had a tank big enough you could upload 200 litres of gasoline at 144 kg, add 10 kg for water in the radiator and you"ll still be able to pack in 6 more kg of nuts, crackers, drinks and other stuff to keep you occupied during 10 hours flying!However, as the resident beak I should also point out that many of the Euro Gyros have published manufacturers gross weights of 550, 500 or even 450, to comply with the appalling regulatory mess that European recreational aviation has become. I can"t provide an easy answer to the question of whether it would be proper for an Australian registered gyro to be loaded up to 600 kg in circumstances where the manufacturer mandates a gross weight of 500 or 550 kg. All I can say is if I were called as witness in an inquest I would say that ASRA wouldn"t be too troubled by a gyro being flown above the manufacturer"s gross but at or below the CASA 600 kg, because all of the scientific and academic literature makes it abundantly clear that higher weights means increased rotor rpm and reduced rate of climb. The gross weight question is simply a question of performance, as distinct from structural integrity. Remember, however, that ASRA requires a minimum rate of climb of 250 feet per minute. If your gyro won"t make that it"s either underpowered or overloaded - 2 sides of the same coin.It would make things a lot simpler legally if ELA, Auto Gyro, Magni, Xenon and Brako all followed ArrowCopter"s lead by publishing their gross weight as "...up to 600kg, according to national rules applicable in the jurisdictions wherever flown."

[RickE]

Thanks for that Mark,When I plan for my X country trips I work on 500kg as my MTOW and on my flight to Wondai last year I had the gyro loaded for part of the trip as you have described ie two 90+ kg males, full fuel and a bit of luggage and it took forever to get up to 4000" to clear the great dividing range at Murrurundi. If I had an extra 100kg on board I think I would still be trying to get over the range. I think for a gyro to fly weighing 600kg it would need a lot more than the 115hp I"ve got to play with.

[birdy]

Anather foot or so on each blade will make a hell ofa difference Rick, and be more efficiant than just strapn on more horses.

[MadMuz]

Anather foot or so on each blade will make a hell ofa difference Rick, and be more efficiant than just strapn on more horses.I was thinking about that same thing, Birdy. can the rotors he has have a longer hub bar fitted?

[RickE]

The gyro I was in on that trip was a Autogyro Cavalon with a 914, the standard rotors are 8.4 m or 27" 6" extruded aluminium. The Germans do have longer blades which a friend of mine is trialling, be interesting to see what he says!

[Brian]

You guys need to find some nice slim lightweight

[MadMuz]

Yeah, I have seen some people with the root strap type blades steal a few extra inches by moving the blades 2 bolt holes out under the straps from the hub bar, like on an MTO not that I think that is a great idea, but a longer hub bar might be able to be ordered? I know some of the horizontal bolt blades cant do anything like that, so just thinking out loud

[mad max]

Back to the original thread which was about the helithruster apparently the craft that was clocked twice at 10 LPH had an EJ22 not an EJ25 engine. I can no longer modify what I type on the forum. The modify option has disappeared.

[birdy]

An ej22 at WOT burn,n 10Lph??**Hell, them valves wont last a lap round the hanger.