Crane Fly Light , Autotogyro Trainer , For experienced pilots trying autogyros for the first time.

[Deyrick Gibbins]

No problems Tom, just had two more flights with CFL now rain has stopped.

Bit off topic but what was the reasoning for using the 50mm GF circle/washer with the GF Delta Plate on the Auto G and is it glued.

My thought was that maybe it was to add some thickness to the plate where it is secured to the head bolt rather than just 0.8mm between two nuts, I cannot see needing it, to stiffen the plate as the standard CFL or SFH does not use it.

Deyrick

[Malcolm - coolwind.co.uk]

Deyrick,

I think sunday evenings tend to be Tom's night out, so I'll jump in if I may,

I think its optional whether you choose to glue the circle or not. It doesn't need glueing.

The purpose of the GF Circle is to present a little more stiffness to the plate if the blade wants to move downward (doesn't happen in flight), and prevent a boom strike on landings/arrivals

Malcolm

[Deyrick Gibbins]

Thanks Malcolm for the insight, I suppose the Auto G mast is a little shorter than the SFH as that does not use a stiffening circle and if you did not cut down the wooden blades for the Auto G they would likely chop the top off the rudder without the circle.

Will have an in depth look at Toms conversion.

[Tom Wright 2]

Deyrick

Just shout if I can be of any help, and note I managed to get a slightly longer blade by trimming the fin back which resulted in a blade length of 403 mm.

Tom.

[Tom Wright 2]

Hi All

For those who are contemplating locating the CFL rudder/elevator servos behind the mast instead of either side the boom I flew a model today that had been converted to this lay out.

The cog is moved forward and so some pitch re trim is needed, my model required 10mm up trim referenced to zero but more importantly the forward cog results in less elevator authority particularly at low speeds which was, on this occasion ,offset by changing the elevator rates from 100 % to 140 %.

It's worth noting that operating the model with insufficient elevator authority can make things difficult particularly during turns and round out, my model was flown on 1A and 1.3 A lipo's in near calm conditions , with no significant changes in handling after the new trim setting and rates were set up.

CFL Builders are much more likely to end up with an easy to fly model if built to the original specifications and trimmed correctly,then after getting their auto gyro wings mods and updates can be tried using the acquired knowledge of how such machines should fly .

Moving the servos forward has it's advantages and does result in a neater lay out , but if designed in from the start I would consider reducing the nose length so up trim was not required and elevator authority was optimal.

Tom.

[Deyrick Gibbins]

Could you not just have moved the battery rearwards a bit, its on the bottom with velcro.

That would keep the same CoG / Hang angle and no need to alter trim or throws.

I would have done that to check balance before flight.

I may move my servos to the mast position as mine needed a small amount of lead and front of battery past the firewall to get hang angle right even though motor is a bit heavier than the 1800Kv motor in the PDF, if its advertised weight is correct at 30g that is, my1450Kv is 38g  40 with X mount (used digital scales).

 

Deyrick

Edited By Deyrick Gibbins on 15/10/2013 21:32:30

[Tom Wright 2]

Hi Deyrick

I still had to add up trim with the lipo in the rear position, however the model is very tolerant to cog changes and I have found it will still fly at different settings, but there will be an optimum that produces the best handling. My point in the previous post was how does a first timer know how a model should fly, and any changes from the original can change that perception, or even result in failure.

It is likely that every model of the same type will end up with slightly different trim settings so it's important to stick to the original design and start with the recommended trim settings as a starting point prior to the trim flights. Pilot preference good or bad is another factor that can affect final trim settings, but you have already gained your AG wings and now you have a reference to aim for when making any changes, so if you move your servos I would anticipate that any re trimming would be easy . This highlights the difference in making comments to first timers that have not yet flown auto gyros, and the ones who have.

I certainly prefer the servos forward mounted and will include this as a feature if a V2 is built.

Tom.

Edited By Tom Wright 2 on 15/10/2013 22:15:51

[Deyrick Gibbins]

Thanks for the update.

It may well help the balance on mine as the 10mm square spuce gave it a rearwards balance, hence the need for small piece of lead and battery overhanging front even with a bit heavier motor.

Did you ever weigh that 1800Kv Emax/E Power motor to see if 30g quoted is correct.

May well do mod tomorrow as raining most of day.

Got a good bunch of flying in today, 5 CFL flights and a dozen or so flights with various of my planes.

Deyrick

[Malcolm - coolwind.co.uk]

Deyrick,

I can confirm that the Emax Motor does weigh 30g, (32g with prop saver), but with no connectors fitted and the prop weighs 5g

Malcolm

[Deyrick Gibbins]

Thanks Malcolm, I have double checked the weight of my Turnigy motor it is 44g with connectors and X mount but excluding prop saver and prop, so say 12g heavier than the one in the PDF..

Deyrick

[Tom Wright 2]

I recon that extra motor weight would balance your slightly heavier boom . ,

Tom.

[Tom Wright 2]

Had an invigorating hour flying the CFL yesterday with the forward mounted servos and battery located behind the undercarriage.
1A and 1.3 A lipo's were flown with the elevator trim set to around zero .

The model climbs quite steeply at full power but is not wayward, a little forward stick pressure results in a good turn of forward speed, and reducing the power setting to half returns the cruise speed recommended for initial flights. I prefer my auto gyros to climb when power is increased as this keeps speed down and gives terrain clearance when in the hands of a newbie, this also makes turning easier with little tendency to dig in even when over controlling.
Pitch trim did change when the 1,3 A lipo was fitted but not enough to cause pilot concern , the 1A was flown in the standard position and then changed to the rear mounted location the pitch trim change was not dramatic and confirmed to me that cog tolerance on my model is good.
Different cog locations did not noticeably effect roll trim , or the ability to auto rotate power off in an easily controllable way.
Elevator authority was good throughout the trials and balanced well with the roll control feel ,with no sign of twitchy responses .
Fight maneuvers included loops, stall turns , max rate turns, flat turns, high speed passes ,low speed passes , touch and go, roll to a stop and rog,
My assessment may not  exploit absolute Max efficiency but for me at least I found the model very easy to fly with no nasty surprises occurring in any phase of flight explored during this session.

Tom.

Edited By Tom Wright 2 on 18/10/2013 02:39:28

[Tom Wright 2]

What went wrong here ?

[Tom Wright 2]

I have some ideas just wondered what you guys think ?

[Martin McIntosh]

Looks like a dire lack of rotor speed to me.

[Martin 10]

Hallo, Ek hoor julle praat Afrikaans, but I will write in English.

Been there , your run off seems to be to long for the blades to pick up speed. In no wind conditions I just walk to get my blades to spin up. Mabe your shims for negative pitch is not enough. Where are you from - maybe I can help. l am from Springs Gauteng and had many success flights with my Crane Fly.

Martin

[Malcolm - coolwind.co.uk]

I agree with martin,

Wrong launch technique. Even in no wind conditions you should not have to do more than a very slow walking pace.

Give the blades a quick spin with your finger, hold the model at 90 degrees, (ie vertical) start a very slow walk, bringing the model to 45 degrees, the blades should be spinning at high speed now and at the last moment bring the model horizontal and launch with the slightest push,

Malcolm

[Tom Wright 2]

Guys thanks for the input and, hello again to Martin. The problem here is the chap in the video, who I think is Chris, does not post here, and I had no idea that he had built a CFL until I came across the video.

The model looked as if it was built to plan, with the exception of the tail fitted back to front and two servos have been used instead of one. Those differences would not prevent the model flying.

The poor chap doing the running clearly did not appreciate the rotors should be up to speed with a walk forward even into very light wind conditions, so we can only conclude that the rotor was binding or the shims were not fitted correctly . The other vague possibility would be severe slip between the prop adaptor and shaft .At least the model appeared to be undamaged after its ungainly contact with tarmac.

Martin suggests that Chris is in SA so, Martin if you don’t mind me asking, could you try and track him down and offer some advice, as Chris is probably feeling a bit disenchanted with autogyros right now .

Tom.

[Martin 10]

Hi Tom,

Yes still watching here from the sideline.

These guys are speeking my language. Nobody is posting on our local website either , so I am still on my own mission.

I will keep an eye on the forums and see if they popup somewhere.

Regards and keepup the good work.

Martin

[Tom Wright 2]

Thanks Martin .

Regards

Tom.

[Martin 10]

Spoken to Chris Marx today. Will meet with him on a weekend and I am sure his CraneFly will be airborn in ajiffy:

Martin

[Tom Wright 2]

Martin

Great news ,thanks for taking the time to find Chris ,hope he is not to far away? The model looked to be well built so it will be interesting to know what the problem was.

Tom.

[Martin 10]

Ok, first problem is Chris made the head from aluminum plate, so there is no flex . I will get his address and send him a flex head if he hasn't find something by tomorrow. Chris is about 100 kilos from where I stay,
Martin.

[Martin 10]

Hi Tom, This is the head,

Martin

[Tom Wright 2]

I recon the model needs some Martin magic before further attempts. The aluminium delta plate was a big surprise , and I can also see that the tail appears to have the tip tapers reversed, the undercarriage is fitted way back, and the lipo is in the nose box.

Tom.