Crane Fly Trainer Autogyro

[Craig Carr]

Thanks Tom,

Got the PDF as well. Will get the bits and bobs from the model shop next week.

Regards

craig.

[Tom Wright 2]

Just fitted out another Crane Fly with HK blades and tried making the 1/64" shims a little narrower .

Trials suggest the minimum width is 3mm and the max width 4.5mm . The 1.5 mm difference has a marked effect ,and requires pitch trim to be reduced as the shim width is reduced . So 7-8 degrees positive pitch trim should be enough for the narrower shim .

Of course the pitch trim will also depend on the AUW .These guide figures are based on 24 oz AUW including a 1.3 A lipo .

Tom.

[Tom Wright 2]

Rich has just raised a good point over on his FF thread .....The HK head ball joint push rod connectors supplied are not threaded to suit 2mm threaded rod ,so it's a good idea to change them for these . I have used cyno to secure the 2mm rods but changing them for correctly threaded types makes a good secure job .Thanks Rich for the heads up .

Tom.

[Tom Wright 2]

An interesting situation at the field to day as the wind was very light but enough to get spin up on the HK blades fitted to a Crane Fly.

So as most of the session was booked for teaching I had a good early sortie, and then for the next hour concentrated on the fixed wing student . When the student was ready for a break I fired up the Crane Fly for another flight, but as the wind had dropped to absolute zero spin up was not fast enough for a rog or launch, so I switched off and went to talk to a guy that had an early set of my tip twist blades on his Autogyro .

After a chat he said, "watch this" and taxied to the hold opened the throttle progressively, and took off ! ....Humph......so much for progress .

Tom.

[Gaz Elliott]

Hi Tom , still not tried it yet been busy completing my dissertation . All done now . Remind the student that take off is optional , landing is mandatory an as such is the more difficult of the two. Landing is a crash... It just depends how you control the crash!!!!!!

[Grasshopper]

Tom,

having snapped the mast of my Fire Fly - on the first flight, I have repaired it but put it to one side and made a Crane Fly as if I have further accidents (if !!) then repairs will be easier during the learning process.

I have a set of HK blades and (wanting to conserve the Fire Fy set) I will use these on the Crane Fly and also the 'borrowed' FF head. Question is can I use the head plate 'as is' or do I need to move the blade mount holes in. The Fire Fly holes are 55mm from the plate centre and you recommend 20mm from the apex of your CF plate which gives 45mm from the plate centre. Yes I could drill further holes but don't want to weaken the plate.

Peter

[Tom Wright 2]

Hi Peter.

I have flown the the HK blades on the Crane Fly using the standard 4.5" 0.8mm plate at 20mm and 30mm in from the apex . TBQH at this stage I have not had the opportunity to experiment to optimise the best position , but either works fine for initial flights.

If you use the 4mm wide 1/64" shim spin up is easy in light winds but results in lower lift more throttle to get away and lower rate of climb . This set up could be better for first flights which if possible should be be done over long grass /soft ground as the model will then usually survive a failed attempt .

As I have suggested many times several trial walks forward into a light breeze to get used to correct spin up speeds can be very helpful , and closing the throttle immediately if ground contact is inevitable will limit or in many cases avoid damage.

Assuming correct spin up is achieved roll trim is by far the most likely thing to catch you out , my model gets away well with 4 degrees right ( looking from the front ) but this setting depends on many other factors and usually has to be adjusted after observing the flight path during the first attempt.

Hope this is of some help.

Tom.

[Grasshopper]

Thanks Tom, interesting. If we can talk about blade mount hole position in terms of distance from the centre that takes out the difference in plate sizes between the two AG's. Also it is this distance which I assume is important.

You have tried hole positions 45 and 35mm from the centre (20mm and 30mm in) - but in fact the FF plate has the holes 55mm from the centre. It is tempting to drill another set of holes in between your test settings at 40mm from the centre or do you think for my initial flights I am being too picky? (just one of my faults!)

Your other notes and hints will be invaluable as I have no one to advise me here on the ground as this is the first AG any of my French flying friends has ever seen.

Peter

[Richard Harris]

Peter,

Good luck with your Crane Fly, I hope you have more success than the FF I feel like I have let you down!

Tom,

I do find it confusing that right trim is added looking from the front but its left trim that is actually being added on the transmitter or am I confusing myself?

Wouldn't it be easier to say left trim looking from behind like the conventional way.

Rich

[Grasshopper]

Rich,

not at all - the Fire Fy is just too nice to smash again in a beginners accident. When I get a couple of flights with the Crane Fly under my belt I will swap the head over and have another go and after the feedback you have all given me from my short YouTube video I am sure it will be fine.

What do you think about the blade hole placement - that is I have swapped the FF head to the Crane Fly so can I just bolt on the HK blades or should I be drilling some new mount holes perhaps in a little?

Peter

[Tom Wright 2]

Rich.

I feel quite certain that it's not a case of letting Peter or anyone else down , as it's very easy for a first timer to get things wrong , even with the best of well designed models .

It's the challenge of achieving success that makes Autogyros so engaging ,and as I have said before it can be so easy once the fixed wing hat is removed and the "penny has dropped"

Your dead right about the roll view position , I always took the view from the rear but some time ago following someone on the thread getting confused ,I stated suggesting view from the front .

Either way is fine but as you say the rear view is more intuitive in terms of adjusting TX trim .

Tom.

[Tom Wright 2]

Peter.

I have two Crane Fly's operational with the HK blades ,both on 4.5 0.8mm plates ,one has the blades at 40mm to centre and the other at 45mm ,both fly well in terms of first attempts.

If you are using a 4" 0.8 plate then the hinge dimension is smaller but the compliance resistance from rotor bolt to centre is higher so using the existing bolt holes should result in a useable flapping range .

The set up may not be perfect but if you can get some air time... then experimenting to find the sweet spot can be interesting . BTW from my observations the FF design is an example of a well optimised set up but using the HK blades does require more back trim as they have less area.

It's a shame you don't have a mate at the field with Autogro experience,as this is an easy way to get the model trimmed and flying all ready for you to take over.

Tom.

[Grasshopper]

Tom, thanks for echoing my sentiments - and at the risk of labouring my point!

I have 'borrowed' the complete head from my FF for the CF and the blades are mounted on a 120mm plate (about 4.5" and the blade holes are 50mm from the centre and that is quite a way from your 40 / 45mm. This is why I was asking if I should drill another set of holes say 40mm from the centre. I am just concerned that the two sets of holes may weaken the plate enough to make it fail.

Peter

[Tom Wright 2]

Peter.

Since my last post I nipped to the field with a Crane Fly that has had the blades relocated at 48mm from rotor bolt to centre....... no problem at all it flew well ,although theoretical flapping resistance would be on the low side.

I have often drilled extra holes in plates and to date not found any weakness developing, I have also filled in holes by using GF dust and cyno ( masking tape under the hole ) .

I would try the existing holes first and observe vigorous spin up in a breeze ,if the blades are tracking reasonably and not going into extreme flap excursions and you can feel the model pulling upwards with a force at least equal to the model's AUW then it should fly ,as the loads in normal flight should be less than the static test.

I always do these checks with everything switched on as if ready to launch .

Tom.

[Grasshopper]

Thanks Tom, I really appreciate that - must be great to have a test site so close by!

I only have the servo rods to finish this evening and then to stick on the sides/nose cheeks which I have combined by not cutting square side plates but growing them to provide a little artistic feature up front. Not my forte is art I am afraid!

Weather here is poor with constant rain showers and strong winds but Saturdaty looks better so fingers crossed.

I have made a series of tests with the FF - blade spinning in a breeze and it generates loads of lift. I will repeat these with the HK blades before I take the plunge.

Watch this space - thanks again, Peter

[Tom Wright 2]

Peter

I could not have attempted all the stuff I do with Autogyros without the "on the door step field". In the early days crash and mend ,and back for another try could easily be done within the hour .

Just a reminder when attaching the control rods to the ball joints , do use a method that eliminates pull out or movement .

Tom.

[Tom Wright 2]

Braved the cold damp weather this afternoon to have another go with the Auto - G fitted with the 3" GF delta plate and single bolt blade fix.

I also increased the blade bolts to 3mm diameter ,as the original just looked to thin to be credible.The model flew well ,with nicely balanced pitch and roll feel , and reliable spin up in the light breeze.

Tom.

[Maxy]

Hi Tom. This blog of yours is amazing the information is so very useful. After crashing the Dag I have been on stop waiting for material & bits for the Cranefly & HobbyKing have told me to expect a wait of up to 30days for the auto-G as its coming from Hong Kong so I cancelled it & shall wait for UK stock. With regards to your Cranefly, which would be the best set up as an introduction to autogyro flyng? The favoured blades appear to be of your design with a T/E twist at the end of the blades.

1) A fixed rotor mast head, with just basic rudder & elevator.

2) A fixed pitch setting with servos for roll (aileron) control elevator for pitch & rudder for ground control & yaw in flight.

3) Fully moving head with pitch & aileron through a mixer. & possible rudder on left stick.

I am getting on a bit & have always flow single stick with throttle left up and down. So the less complication would be the easiest to me. I now realise that autogyro flying is a little more complex than fixed wing as you have to know when those rotors are capable of giving you sufficient lift.

Regards Max

[Tom Wright 2]

Hi Max.

To answer your post fully , I would need a little more information about your pilot experience and currency. As you do not have a personal profile to refer to it may help if you could pm me with more details including your location .

As for the model configuration then 1) is a definite no. If you wanted to bash on rather than wait for the HK stuff to arrive then 2) without rudder would be worth looking at . I have spare HK blades and could sort out a single function head.

I have not flown a Crane Fly on a single function head and elevator, but give me a few days to build the model and I will post the results.

I f you are really determined to get your Autogyro wings I am sure this can be achieved .

Tom.

[ken anderson.]

hello tom....mine is finished...i've been setting the head and checking the angle that it's hanging etc.....i've done it several times to make sure its the way it say's on your blog......i have several lipo's of 1000/1800 and 2200m/a all 3s......the 8*6 prop with the 2200's was giving me just under 200 watt's........ i think that for the initial flights that the 2200 may be too heavy.....watch this space for photo's and hopefully if the weather allow's a 1st attempt report......

ken anderson....ne..1..... foodmixer dept.

[Maxy]

Hi Tom , I have been flying RC 3 & 4 function for 36 years sports & areobatic took my A Cert in1983 & have been club instructor for twenty years mainly on Ic. Our club is now nearly all choppers & plastic electric. I really want a fresh challenge & autogyros will certainly provide that,but as I have said before our grass runway is also a challenge its has many mounds & dips on it about a good 75 yards of take off space its common land and cattle use it as a toilet & as yesterday I have had to depoo my model. So ROG will not be impossible but difficult with all the bumps so a light model with easy rotor speed such as the Canefly that can be hand launched as our runway faces direct west & is at the top of a hill that catches plenty of wind is the way I am going. I am a member of the Llantrisant & District model Aircraft Club nr Beddau South Wales. I don't know of anyone local who is at all interested in autogyros, but I intend to change that.

Regards Max

[Tom Wright 2]

Right Ken I will alert the northern home guard. .

I used the 1.8A to maiden the HK head and blades . The final set up depends on the blade shim ,I used the 4mm wide option which give prompt spin up but minimum lift so if you have done likewise most of the 200 W may be needed to climb or check sink during over banked turns. This is not a bad set up for a first try .

Pitch can require course stick movements ,were as roll needs a sensitive touch and degree of anticipation .Some opposite stick may be needed to correct recovery from a steep bank ,with plenty of back stick to keep the nose tracking around the horizon.

If things are generally to plan then insufficient rotor speed ,or roll trim out of stick range should be the only things to prevent getting away into a gentle climb. Keep intently focused on the tail during flight as this helps with orientation.

Here ends the briefing ....best of luck.

Tom.

[Tom Wright 2]

Max Thanks so much for the information, it makes it so much easier to avoid the "Grand Mother sucking eggs " dialouge .

Your flying field sounds very similar to ours ,with plenty of features to keep you on your toes lol.I learned to fly full size at the shortest CAA registered field in the UK , so landing technique had to be accrurate ,with well planned aproaches an absolute nessesaty ,but then I found it realy weird looking at all the availlable space when going in to Birmingham ,and other commercial airports.

Without looking back I am not sure if you have started a build or what parts you have to hand , I can certainly help with a set of blades and a single function head if required , just let me know how I can help as the gauntlet is down to achive Autogyro wings in Beddau.

Regards.

Tom.

[Tom Wright 2]

Made a start tonight on another Crane Fly ,but with a single function head ( roll only ) and elevator .Could have converted one of the others but though I would try a single servo for roll ,and under slung ,detachable under carriage.

Have finished the head ,mast ,and most of the fus so it should be nearly finished by tomorrow night and ready to fly on Thursday afternoon, weather permitting.

This is a design I have had in mind since experiments with the Pipe Lagger Autogyro ,and has come to fruition following the flight trials with the Auto - G , I will use the HK C-30 blades and a simple control mech devised to make roll nice and user friendly for first timers..... I hope ?

Following my idea of shedding lift in favour of super quick spin up ,the air frame should be lighter to compensate, and also even stronger due to the reduced inertia . .....Still won't be pretty though .lol. .

Tom.

[Maxy]

Hi Tom I can see you have been burning the mid night oil, look forwards to the outcome. Keeping the weight down will ease those awkward landings.

Max