A Gyrocopter is NOT a short take off aircraft... 

Hi - I'm not sure if it was the point made but I just want to clarify that the use of the CFI in this film was in no way a criticism, it was used simply to demonstrate a well executed take off needed to be done swiftly. Rotor management - well in this context I'm not sure what you mean. Yes its fundamental at some level so you don't damage the aircraft (i.e. don't allow rotor RPMs to decay) but this film isn't so much for student pilots to pass a pilots course and more to highlight the general performance of a gyroplane and in that context managing the rotors is absolutely trying to get the most performance from them. I don't know any manufacturer or CFI talking much about that tbh. Wheel balancing - again Its not a criticism of that technique either and actually on a rough strip I might be included to get on the mains and protect the nose wheel sooner plus unstick at a slower airspeed. So I'm not a wheel balance hater as some might think. The point of the film is to demonstrate that a gyroplane - despite the marketing claims of many manufacturers - isn't really that quick to take off, certainly if you are going to respect the HV curve published. We can see that by the random selection of pilots 1up, 2 up taking off. It also highlights that the POH may give a take off distance number but you may not achieve that number because you don't have enough skill. I'm not suggesting for a second that this applies to you - I'm just giving a view in your reply - but almost none of the films I've ever made are specifically for a student pilot to pass a course. Yes some manoeuvres will naturally led themselves to a test environment and the advice might align (and I think the advice would work) but passing a course to gain a licence is not all there into flying and student pilots are not the only ones in the sky! Indeed most pilots you read about in an accident investigation are current licensed pilots making the same old snafus because they slavishly follow something and apply the wrong technique to the situation.

But what about takeoff with pre-rotation? I thought those can allow something like a jump-takeoff. Shouldn't pre-rotation be a key tool for short takeoffs?

@@manofsan please watch the video of the Hawk 4 gyroplane it rolled all of 6 inches before lifting in to the air like a full helicopter

It looks very underpowered so I'm sure that doesn't help

Well done. Well explained….

It is STOL indeed.

All gyros can do very short landings. But not all can do short takeoffs. A pre rotator (which most all gyros have now) helps to shorten the takeoff roll m by getting the rotor spinning at xxx rpm’s before the takeoff roll starts. But this gets the takeoff roll to like the average length of a Cessna 172 or 152 takeoff roll. These prerotators may be an electrical motor on the rotor head or most common a hydraulic drive. More rare (and complex and expensive) are gyros with jump takeoff, wherein a mechanical shaft from the engine spins the rotor up to flying speed, and the rotor has a collective pitch lever (like a helicopter) which is pulled which creates the vertical jump, after which the mechanical connection is immediately disconnected and the gyro flies off as a gyro.

Hey Mark - Yeah I think they likely were compared to the modern sport types and that is because they are much bigger entities in that the motor / prop would have generated more thrust and the rotors much bigger and with 3 blades - and that in combination would have been useful to that. You might also factor in that much of the footage of the old aircraft would have been with professional pilots and in part for the camera.

Yes of course the ability to get airborne simply a function of airspeed and rotor speed.

A strong pre-rotation reduces take off roll. High lift blades too. There is a trade off between speed and low speed lift with rotor blade design like with fixed wing design

Thanks for the kind comment. I think you've designed a Cierva C19. In truth wings on a gyro help in flight but the AoA during take off probably mean that the profile that isn't stalled during this phase is a burden during flight. A gyroplane is a short enough take off aircraft to be interesting / capable for most situations and the film is merely a caution to those that may get sucked into the marketing claims of some manufacturers.

​@@gyrocopterflyingclub6148 - Thank you for replying and for the explanation. You are right about the manufacturer's claims. I myself was falling for it. Haha... Not that I was trying to be clever. It is simply that I am curious about the technical reasons. It bothers me the fact that gyros are evolving towards clumsy "not-affordable" luxurious vehicles instead of utilizing the overwhelming new tech in order to make gyros more wind independent and to follow Bensen's marvelous philosophy of "affordable flying".

Yes I completely agree on the direction of the aircraft and in the end once the gap to basic helicopters becomes minimal people just fly a helicopter because they perceive they may need the VTOL even when they fly from the same 3-4000ft airfield they did in a fixed wing! We have lost a little of the fun however take a look at the NANO film that looks a nice aircraft.

@@gyrocopterflyingclub6148 - Great! The NANO does look more like the original and appropriate idea of a gyro. Trust the British, hey? The only inconvenience that I find, for my intended use, is the engine.size of the NANO. I'd like your opinion about the AERO. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9o05hW2dnoE.html&ab_channel=jobahed

Hi - well the club is a legacy/extension of my flying school. Online by subscribing you are part of the club and if you select alerts then you'll be notified when new things happen. Of course meetings are via the webinars that are done at least once per month. There is a small fee but that is just to cover the fact they last over 1 hours [usually 2.5hours] and to allow that you need a professional subscription to ZOOM. If you want to support the club/channel any other way then there is that Patreon tiers, see here:- www.patreon.com/gyrocopter

Thats called a helicopter - I don't know of a single "jump take off" gyroplane available and on sale to the general public anywhere in the world.

Pre rotation cuts down the portion of take off roll required to get the rotor up to speed

@@gyrocopterflyingclub6148 I can think of 3 offhand.

@@neuralwarp Really? Honestly I can think of gyroplanes that are more "technology demonstrators" with that ability but I don't know any manufacturer offering a gyroplane with a jump take off functionality that is currently on sale to the public. Happy to be educated otherwise.

Olá Sandyfraser,sou brasileiro e estou construindo um girocoptero, você conseguiu construir o seu? Grande abraço.

Do you have a specific model in mind?

Cartercopter made a technology demonstrator - thats the most recent one i can think of.

Some actually do.a sort of gear that you disengage after.

Hey Ben - that is interesting. Yes so in 99% of cases the aircraft is going to take off into wind so airspeed will likely always be +ve initially all be it at a varying value. On the accel. I see your point but again it will have so many variables that that too will be impossible to give anything more meaningful [IMO] than the rough numbers because it will vary with pre-rotation speed, initial airspeed, angle of attack throughout the take off roll and the angle of the fuselage as it lifts. In terms of material change have you any colour on the variation between the rough calculation highlighted and a more detailed view? i.e. aircraft A has initial airspeed of 0, final of 60mph and takes 30 seconds and constant acceleration. Aircraft B has initial airspeed of 10, final 60 and takes 30 seconds and the acceleration isn't constant but increases. Mathematically I can see the point but at the same time it starts to disconnect from reality because of the number of reference points you'd need to add to your equation surely? So accel at time t, t1, t2, t3.... at some point you surely have to approximate and then question just how big the delta is of any error and see if it kind of works? i.e perhaps in a lab looking for an absolute number we might accept less delta but for a pilot thinking as a pilot and a take off distance of [say] 1000m and an error of 10m it doesn't matter. If you see my point.

As an aside I was reading this and my head fell off:-web.mit.edu/8.01t/www/materials/Presentations/Presentation_W01D3.pdf

@@gyrocopterflyingclub6148 I think it's something that would have to be established experimentally, as you say there are a lot of factors involved. I don't know how flight simulators handle the problem, it may be computed or a simpler approximation could be used. Part of the reason I made my previous comment is because the logical, but dangerous, next step is to calculate the value of a (acceleration). That's the other variable in the SUVAT equations and can be calculated with the same variables you used to calculate distance. With a, you could then calculate a theoretical take-off distance... but, as it relies on the assumptions that initial speed is 0 and acceleration is constant, that would be a dangerous calculation to rely on. If the acceleration is greater towards the end of the take-off run (but time remains the same), then distance required is less, as proportionally more of the time is spent at a lower speed. How much difference that makes would depend on how acceleration varies - and it probably won't be simple! I'm a helicopter guy (although gyrocopter-curious 😂) and I don't know how applicable this would be to a gyrocopter, which I assume is fixed pitch. The basic starting point is force = mass x acceleration. Mass is effectively constant so acceleration is proportional to thrust. Ignoring vertical or yaw forces, that leaves thrust and drag. The difference between those two is the force available for acceleration. Generally speaking, during a normal takeoff for an R22 (using the profile recommended in the POH) with a constant power setting, thrust is going to increase markedly from 0 to somewhere around 24 knots, then more or less level off. Drag is going to decrease from 0 to 53 knots, then increase. So the net force, and thus acceleration, will increase significantly until 24 knots, then more slowly to 53 knots, then decrease above that. I couldn't give any numbers for how that varies, I generally just worry about whether I can clear the obstacle ahead - and have a decision point and plan for if I can't! * I realise it sounds counter-intuitive to say thrust increases and drag decreases as speed increases. I'm happy to explain more, but in a nutshell, the rotor gains efficiency and the reduction in induced drag more than compensates for the increase in parasitic drag. If the same applies to gyrocopters, apologies! At the end of the day, I wouldn't try and calculate take-off distance using a basic formula (unless it's been established by a manufacturer). You might get a number that's in the right ballpark, but the level of uncertainty is likely to be hundreds, not tens, of feet. You could do some testing to establish some numbers, but even then, they will vary with factors such as density altitude and even takeoff surface. If in doubt, have a plan to bail out!

@@gyrocopterflyingclub6148 Ah that brings back flashbacks of my degree!

It really doesn't do much to clear 50 foot obstacle. That's the standard definition of takeoff distance. To achieve 300 rotor RPM, you end up going to almost full power, then you pull the stick back somewhat and the drag slows you from accelerating to Vx (48 knots), so by the time you reach that to safely climb up and gain altitude you really are close to where you were. To me the 300 RRPM seems to be more of a gimmick for marketing material. If you look at their POH and actually see what it says about takeoff distance (standard takeoff distance to clear 50 foot obstacle), the length given is no different than when I pre-rotate to 200 rotor RPM

Hi - its not a simple answer. So if you have time take a look at the other films I've made in particular this one:- ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-RqyEFgWF92o.html Specifically on the 300rrpm element - if you want to make the most of it you need two things. 1) you need to adopt a take off technique closer to one I have suggested for around 3 years now and if you google "AutoGyro 2017 Sport POH" and look at short take off in the POH. That explains the issue with drag - as I explained it here:- ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-kW65IY39MPU.html If you combine that with a bigger motor - so Rotax 915 power - it makes a difference, and I say that with practical experience of the aircraft, not just paper theory. If you use 912 power then if you use a "legacy" take off technique i.e. look to hold a wheel balance and get there on part power - then actually you take longer to get airborne because of the huge increase in drag.

Agree/disagree Abid - see the other reply. The key is dealing with the drag. The actual data however given by AutoGyro is poor in terms of the detail but having flown all AutoGyro models a lot (you have poor choice of aircraft in the UK) 914/915 and 300+ rrrpm makes a difference. Actually in a 915 motor aircraft you are forced to not use full back stick for long because you'll get dumped on the tail fast!

@@gyrocopterflyingclub6148 I think what you are pointing to is that with 300+ RRPM the stick should not be all the way back but somewhere near neutral to take advantage of this pre-rotation to reduce takeoff distance to clear 50 foot obstacle. Phil yet in the other video posted in your reply at 1:45 onwards, the takeoff distance to clear 50 feet shown with 320 rotor RPM pre-rotation one up seems basically the same distance I see in an AR-1 914 one up pre-rotating to 200+ RRPM. So where is the advantage? Now I did not get to try it one up when I just trained a student who owns a MTO Sport 2017 914UL and we tried this 300 RRPM takeoff technique with stick somewhere near neutral. May be I am missing something and I would be happy to know any tricks or anything to try. He will be back to take final prep hours before his checkride sometime this week. We can try them. Don't be shy to let me know. I am not an expert pilot by any means. I have not flown 915 MTO 2017. I have only flown AG915 once but it was not properly rigged at the time. But in theory yes you have to overcome the drag of the spinning rotor to get to Vx to have a safe climbout and not settle back down. You have to do that without letting the rotor RPM perish as well so its a balance. The directions to conduct this takeoff in the POH are not very good at the least. We have a short field takeoff, demonstrated by Greg here but Greg has thousands of hours. There is also a 10-12 mph headwind here but it requires keeping pre-rotator engaged as you pull stick back and move forward. Again a delicate balance. Its also hard on pre-rotator components especially the upper U-joint and hence should be used only when really necessary and upper U-joint checked and possibly changed on condition ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-iMb5BOm_GYg.html

Hey matey - the take off performance compared film at 1:45?? If so both aircraft are pre-rotated to 200rrpm and if you are looking at that film then at the end of it (around 3:29 onwards) shows the difference (one is +100ft the other is still building airspeed). OK something to try with the 17Sport - is pre-rotation to 320 means power is very high anyway at brake release. Just bring the stick back to halfway (thats the subjective part which really needs building up to because as you know its better to have it further back than not enough initially) but brake release - and full power into the boost - and it should unstick within

How many of each model have been sold?

You have to make the wing. You cannot outrun the rotor. The result of that is blade flap and a flipover

Ha this is a current debate. They can perfectly start their ground roll with 100% throttle but the problem with the legacy technique of full back stick maintained until the nose wheel lifts is that many get behind the aircraft - which means the aircraft is dumped on its tail. So to get around that the majority retain the “keep the stick fully back until the nose wheel lifts” narrative but introduce a part throttle set off to dilute the speed the process happens. Of course now that means a great change when the pilot really wants to get off... hence why the accident rate is what it is IMO.

Gyrocopter flying club - What do the aircraft AOM’s stipulate? They must describe the technique required. Every fixed wing aircraft I have flown (commercially) to date insists full power must be set by 60 kts in order to achieve required T/O performance. The figures in all manuals are based in take-off power being set. What do gyroplane manuals say?

This is another problem which I intent to cover in a separate film. The manuals are frankly gash. They don’t give clarity about how their numbers are achieved- indeed I saw a manual from the Spanish manufacturer recently that didn’t even give a distance to clear 50ft!! In the UK the CAA airworthiness dept have dropped the ball on this kind of thing.

to take off verticaly this need a very strong rotor prelauncher able to reach more than 400rpm , a heawy rotor (to increase the inertial) and a collective pitch control: such Gyros are called jump gyros...For short take off this need a strong rotor prelauncher able to reach close 350 rpm and a very good power to weight ratio...basicaly a gyro with standard rotor is same as a fixed wing aircraft in the difference that the rotor rpm should be closely monitored because loss of RPM with too steep climb at take off= death...

@@leneanderthalien check the existing models!

We have to be careful. If you look at my channel videos you will see a lot that track a potted history of the aircraft from their invention all the way to today. In that series you will come across the Avian and that aircraft had a "jump take off" so would fit your narrative but it was certified in the helicopter category and they sold no aircraft. Today the gyroplane is almost 100% 2 blade teetering rotor and they are not short take off.

@@gyrocopterflyingclub6148 Depends on the design. 99% of the gyroplanes out there are pusher configuration. Tractor configuration would yield better results. The little wing autogyros are converted fixed wing airplane fuselages and use rotax engines on them and do ok. A newer tailwheel tractor configuration would have to be designed. However, The Twinstar gyroplane that I did some training in had an O-320 Lycoming engine in it and got off the ground faster than any stock Cessna that I had flown, and that was with two people in it. The old style blades are better but more complex and expensive to build. It seems to me that everyone is stuck on designing gyroplanes that look like fighter planes or sports cars. With a pusher configuration you have to keep it clean up front. With a tailwheel tractor configuration it allows you to swing larger propeller with better engine cooling.

Very kind comment actually you know I get confused with the T'down. Its not really something I get hung up on but I do wish if there was genuine opposition to a view then someone could take the time to explain the issue because I guess that is how learning happens.... Hey ho.

@@gyrocopterflyingclub6148 Absolutely right. ... this or that at least have the courtesy to say Why!

What does FAR say about short takeoffs?

quantify "decent pre-rotator"...

Hi - that is very good point and likely why the gyroplane remains firmly in the sporting aviation camp because when it is benchmarked against aeroplane or helicopter it is lacking. Where it works for the sporting pilot are excellent visibility and a relatively cheap entry point in some markets that still allow kit built aircraft. Perhaps the biggest advantage for the occasional sporting pilot is the fact you can land in very small spaces, making for relatively easy emergency landings, and of course you can not stall/spin in.

@@gyrocopterflyingclub6148 Thanks for responding! But why, from a physics standpoint, are they not capable of a short take off? I have read that some can maintain altitude at as little as 12mph. Surely that this means that that particular craft would only need to accelerate beyond 12mph to take off making for a very short take off roll. Additionally, why are they no longer made with the jump capability?

@@Make_Boxing_Great_Again Yes on the numbers you give I would agree but the 12mph number is more like 40mph and so that changes things a little. The problem with all is regulation tbh as regards "jump take off" and then on going maintenance and of course pilot training.

Does anyone outside of the guy that built that aircraft fly or own something similar? So yes for maybe 1 person in the entire world you have a point, for everyone else this video is relevant....Have a lovely Christmas.

But then a 30mph would make a fixed wing aircraft equally more effective?

yes although I suspect we'd create a new set of issues

@@gyrocopterflyingclub6148 JATO units then?

Apparently my attempt at humor failed........

Tad Johnson hey no. no sorry just missed the JATO comment :-)

Yes most definately

When they nosedive into the ground

Sure although as a machine to get you airborne, if you keep it simple, they offer great visibility, low storage [because the rotors effectively orientate to the fuselage] and a maneuverable platform - far more maneuverable at low level than fixed wing. Sadly in the UK at least the aircraft have shifted to become overly complex.

130 - 150 hp Yamaha is a great Gyro powerplant. See Tango Gyro. They run circles around a Rotax powered Magni or equivalent.

Made up issue? Explain?

@@gyrocopterflyingclub6148 Exlanation: for 99% use cases it is a STOL aircraft and for 1% it may not work as a STOL aircraft. This video is about a non issue.

@@PaulValickas You are fundamentally wrong because you assume [incorrectly] that the take off profile matches the need and it doesn't. That aside there are countless accident reports with gyroplanes hitting boundary fences because the pilot in command assumed he could exit a field that he couldn't - including very many featured in this channel.. If you care to look at the very many films I've made you'll be illuminated.

@@gyrocopterflyingclub6148 Fundamentaly wrong? Really? Oh well, I guess we live in a flat world of alternative facts so my apologies to you sir, I am convinced by your argument: gyro is not a STOL aircraft. All these yt videos about short take offs and landings are fakes and makers of these aircraft are lying to us.