Here is a list of all the postings Mike Freeman has made in our forums. Click on a thread name to jump to the thread.
|Thread: Flying Wing Power Zoom|
Thanks J D 8
I'd imagine without the down thrust on your Zagi you'd be having the opposite problem to me with your model diving into the ground, thanks to the nose down moment a horizontal motor shaft would produce!
My model has a reflex section plus some reflex on the elevons and sweepback to the wing.
The following photo shows the TE of the wing at the root where it slots into the new fuz I've built for it.
The instructions for the glider suggest an additional 4mm of reflex on the elevons but after flight testing on the slope and some CG tweaking using the dive and inverted tests I ended up with the CG at 20% MAC (210mm compared to 197mm in the manual) and 2mm of reflex - this is the CG and reflex I have set up on the power version at the moment. I'd understood that 20% was the max but, after reading up on flying wings a bit more, it looks like I could go back a little further which I'm going to try.... Trouble is I've been warned, going back too far on a flying wing can be more disastrous and unrecoverable than a conventional model!! So it'll be small steps!!
You said... The flying wing has little pitch damping and so can be sensitive in this area of control. Ain't that the truth! I was out flying my Taboo design (see my avatar) this morning. I set this up in exactly the same way I've been trying to set up this wing and the Taboo flies impeccably.
Edited By Mike Freeman on 17/05/2020 18:17:20
Yes, my set up is a pusher with the motor shaft in line with the CG. It looks like your Zagi has the thrust line above the CG so the thrust is producing a nose down moment keeping the model level when the throttle is opened. This is what I'm trying to achieve by angling the motor down at the rear but as the prop (and therefore the thrust) is relatively close to the CG I think I'm going to need a big angle (more than the 4degs I have tried) to get the necessary moment to cancel the power zoom but this causes problems with my model as the instant the throttle is opened it pushes the nose down momentarily until the speed builds up enough to produce enough lift - very disconcerting close to the ground!!
I'm going to experiment with the CG location - I think there is scope for a bit more movement there and maybe try flight phases to tweak the reflex to match the flight condition.
The CG's are the same on both the glider and power version and I'm pretty sure my power zoom is speed related. I'm also pretty sure my experiments with thrust angles have been meaningless because the prop (and therefore thrust) are very close to the CG so I'll need some drastic angles to make a difference - a bit like your Sharkface, FB. I'm not keen on those sorts of angles thanks! Plus, with the down thrust I did try (around 4degs) there was a definite nose down pitch when the throttle was opened until the speed built up and the lift caught up - very disconcerting. As a result i'm going to build the motor in at 0degs and treat the zoom by other means.
My club Chairman is a big fan of flying wings and has shared some very interesting info about CG's on flying wings which I'll be exploring. He also suggested using flight modes to change the reflex to suit the power and glide phases which is something else I'll be considering.
One thing I wont be trying is mixing elevator compensation with throttle unless I can time the elevator compensation deployment to match the speed build up to prevent a sudden nose down pitch when the throttle is opened!!
My CG is currently at 20% MAC which I had understood to be the safe rear backstop for a flying wing but it now seems there is scope for a bit more which should certainly help the situation as Trevor suggests.
Isn't this hobby/sport of ours fascinating! Always something new to explore!!
Edited By Mike Freeman on 16/05/2020 21:04:08
I wonder if I could pick your collective brains please?
I've never been in to flying wings but, just before the lockdown I was flying a slope soaring flying wing and actually quite enjoyed it! So much so that, during said lockdown, I've built an electric fuz for it so I can fly it at the club patch.
I'm not keen when models zoom up when power is applied and whenever I design a fuz I always experiment with thrust angles to get it as neutral as possible. I was confident I would only need vertical thrust adjustment and no side thrust so I rigged up my usual method of adjusting the thrust angles on this pusher set up. Hopefully these snaps show the arrangement. Please note, the fuz isn't finished yet and it is still in it's naked, uncovered state - it'll have a proper cowl and a folding prop when done
Each of those shims introduces 1deg of downthrust. So, I could add up to 4degs of downthrust if required - this seemed ample to me!
Now we are allowed to fly again I've been experimenting and it seems that no amount of downthrust counteracts the power zoom when the throttle is opened. If anything, adding downthrust causes a disconcerting momentary drop of the nose when the throttle is opened and then it climbs away unless down elevator is fed in. The best arrangement seems to be 0degs and find another way to cancel out the zoom!!
The thrust line is in line with the CG so there is no twisting moment to effect a pitch change and, to me, the zoom appears to be purely speed related. Actually, when flying it as a glider it would zoom after a dive but that wasn't so annoying for some reason!!
Obviously the reflex is working as an elevator and causing the zoom and I've moved the CG as far back as I dare and the reflex is around half the manufacturers recommendation and it still zooms up, if no elevator correction is applied it steadily goes up and round in a loop!!
I'm thinking this is just a trait of flying wings and I'm going to have to put up with it but I wondered if any of you learned flying wing fans know of a trick to balance out a power zoom?
Edited By Mike Freeman on 15/05/2020 17:46:35
|Thread: Most flown model|
My most flown (and best loved) model is my original OD Taboo design which featured in the Feb 2012 issue.
I've lost count of the number of flights but one memorable one was when a tree was closer than I thought and my Taboo flew head long into it...... I can still hear the sickening sound of splintering of balsa!! The fuz was wrecked back to the wing TE. One wing was split in half and the other had a damaged LE. I managed to collect as many bits as I could and rebuilt it, using as much of the original as possible. It's still going strong. This shot was taken just a few weeks ago!
|Thread: Can Superphatic glue go off?|
Spot on Keith!
My initial question to fellow forumites was "Has anyone else experienced this phenomenon?" and I certainly haven't found the responses fruitless speculation!! On the contrary, they have been very informative.
I suppose I could of gone straight to Deluxe Materials and asked them but where is the fun and education in that!?!?
It looks like others have experienced the same so I have emailed Deluxe Materials and here is their reply...
"Sadly I'm familiar with this issue.We had a small batch contaminated sadly and recalled as much stock as we could.
Product itself it does work the same way its strength and performance were not compromised just its colour.
Glue will work as well as the old one."
So it appears I had a bottle that slipped through the net!! Deluxe Materials went on to say if I wasn't entirely happy they would send a replacement.... Two bottles are now winging their way to me! That's great customer service!!
So, what have we learned....
Thanks for the replies.
Here is a photo for info. The bottle on the left is quite old and looks normal. The other looks decidedly off!!
I haven't used a pin in the nozzle so I don't think its rust. I'll most likely start my build with the older, normal looking, bottle and think about using the dodgy looking one if I run out. I've been using Deluxe Materials Aliphatic and Superphatic for years and love the stuff but never seen this before!!
I'm just about to start a new traditional build but I see my relatively new bottle of Superphatic glue has lost its usual yellow hue and gone a dirty brown colour!!I've tried it on some scrap balsa and it seems to give a good joint but I'm wondering, if used, the joints will stay good?
Has anyone else experienced this phenomenon?
|Thread: Model flying photos you're proud of|
With all this rain and gales we've been having over the last few weeks I thought I'd share a couple of shots from the White Horse MC patch during sunnier times earlier this year.
The model is an FVA 10A Rheinland with a wingspan of 127" making it 1/5th scale. It was scratch built by Vic Green, better known as a locomotive modeller but no mean aeromodeller too! On the sticks was ace glider guider and Vic's chief test pilot Simon Jones.
Here's a recent snap of WHMC clubmate, Pete Searle's E-flite 1.2mtr P-51 Mustang off on another sortie.
Edited By Mike Freeman on 13/10/2019 17:30:58
|Thread: RCM&E Dec 2018 - Ruckus Review Update|
I was out flying my Ruckus this morning, trying to blow the canopy off like you and Frank have experienced. I tried bunts and dives and flick rolls all to no avail...... but good fun nonetheless!!
Just a thought..... did you add the extra air outlet hole as recommended by CenturyUK? See here
Sorry to hear you are having troubles with your Ruckus.
I think your 3000mAh packs may be too heavy. I find the best CG location is 105mm back from the LE - a lot more than your 80mm!! I found a bit of differential on the ailerons helped the roll rate too. Here is the relevant bit from my review.....
Over the next few flights I tweaked the set up to suit a more aerobatic flying style. I swapped the Rx for a 6-channel version and assigned each wing servo to a separate channel so I could introduce a little differential. I finally settled on a CG location of 105mm from the leading edge (just behind the recommended maximum) and surface throws of:
Aileron 25mm up & 20mm down
Elevator 15mm each way
Rudder 35mm each way
With these settings and 20% expo dialled in I had the best of both worlds: Nice easy flying around neutral yet more exciting aerobatics with the sticks in the corners. All this and STILL that insanely slow flying speed is possible – amazing! The greater throws improved the aerobatic performance enormously with snappier rolls and super tight loops easily achieved.
The rearward CG makes the Ruckus almost pitch neutral which means it stays in a dive when the nose is pushed forward, there is just a gentle recovery to level flight when the sticks are released. Moving the CG any further back causes the Ruckus to stay in a dive or even tuck under which some may find disconcerting. Inverted flight requires only an occasional dab of forward pressure to hold level flight and inverted loops are no problem (as long as the LiPo pack is well strapped in!)
I recon you'd benefit from shifting the CG further back which should help reduce the power zoom you mention. I think I added a bit of down thrust and right thrust to mine after a while but I don't recall it being too far out out of the box.
Also, the 11x5.5 prop is more suitable for a 4S set up. A 3S pack needs a 12x6 for the best results.
I hope that helps and gets your Ruckus behaving properly. I'm still enjoying mine - a 3S 2200mAh pack and a 12x6 are just right for sports aerobatics - it won't quite climb vertical but does OK. Maybe the name makes us expect too much but, for a sports aerobatic Hack it does pretty well!
|Thread: Multiplex Cockpit Sx 9|
Mastercrashman - Phew! I'm pleased to hear you got your Taboo back and thanks for your kind comments about it.
Capt - The only way I can find to do what you want is to use one of the 3-way switches - let's say Aux3. Here's how...
1. Assign the timer 2 start (the "Switch" box on the screen) to Aux3 UP.
2. Assign the timer 2 voice activation (the "Start using" box on the screen) to Aux3 DOWN.
3. Set Aux3 to mid position while taxiing out and as the wheels leave the ground switch Aux3 UP to start the timer 2 - switch Aux3 back to mid position.
4. At the end of the flight when the wheels touch the ground switch Aux3 DOWN and Flossie will tell you the total flight time which you'll have to remember as the timer will keep running until you hit the T2 stop button back in the pits.
Edited By Mike Freeman on 15/08/2019 21:18:11
I do find the countdown feature very useful but I thought that having access to the time remaining by a swipe or a switch, when I wanted it, would have meant we would be able to turn off the minute by minute countdown - we don't really need both!! Sadly, it looks like this can't be done. The young lady has quite a domineering voice compared to the soothing voices emanating from other Tx's in the pilots box and I frequently get witty comments from my clubmates every 60 seconds when she pipes up with the time remaining!!
Sorry to hear you lost your Taboo. Did you get it back? I always put my contact details on my models just in case! The original Taboo is still going strong and regularly gets an airing, still one of my favourites!
Assigning the timer to a switch does the same as a swipe - giving the timers time. The young lady still pipes up every minute during the countdown though and I can't find an option to switch her off!!
I tried your excellent suggestion of cancelling the alarm and having the timer count up. This stops her but I loose the countdown feature - she just tells me the time on the timer whenever I swipe or flick a switch. I could use that and stop flying when the desired motor run time is reached but I do like the countdown timer!!
I'm starting to think it isn't possible to silence her - maybe the next update will have this feature.
Edited By Mike Freeman on 14/08/2019 16:28:20
Yep, that's as far as I got too! Quite reassuring that I hadn't missed something obvious but still mildly irritating that we can't stop the lady from chiming in every minute.
I must admit, I thought the "swipe up" option would automatically do away with the regular updates - I, for one, don't need both and it seems strange to have the "swipe up" option AND the regular updates running concurrently.... do folks need that much updating??
The early Cockpit manuals were great - lots of info and examples to help programming - the new manuals not so helpful!! As you say though, the gear is as good as ever!
Hello Cockpit SX fans,
I've just updated my SX9 to software version 1.40. Lots of useful additions there. I particularly like the "swipe up" for Timer 1 voice updates but does anyone know how to turn off the regular Timer 1 voice updates? I'm constantly ribbed in the pilot box when the German lady pipes up with the time remaining every minute through the flight!! I'd much rather just rely on a "swipe up" towards the end of the flight to tell me!
|Thread: Small motor ideas ?|
+1 for George at 4-Max.
He's just helped me select a motor and ESC for a little aerobatic job I've designed. He's a very knowledgeable chap and the range of motors he has is immense so there should be one to suit most situations! My little model flies great with the 4-Max gear on board.
I too have used several of his LiPo packs. He says on his website ..... "You won't be disappointed with 4-Max LiPo's". He's right! I'm not disappointed - I think they are great... 40C rating and, as Bruce says, not prone to puffing. Reasonably priced too!!
Edited By Mike Freeman on 23/06/2019 22:24:55
|Thread: Model flying photos you're proud of|
I thought I'd add a few of my favourites from recent flying sessions.
The shabby looking slope soarer is my brothers Boomerang to which he had taped a Mobius camera (viewing the results made us queezy!!) The others are clubmates models at the White Horse Model Club.
|Thread: Where can I buy Profilm (Oracover) by the metre?|
Sorry for the late reply - the day job inconveniently got in the way!!
The Rapid Models stuff looks interesting but it is a fraction of the Profilm prices is it really as good? I find Profilm very easy to use and if the Rapid Models stuff is as good (both in quality and application) it is certainly worth considering.
West London Models do, indeed, sell it by the metre and have a good selection.
Unfortunately, BalsaMart don't have the colours I'm after.
That's brilliant thanks!! WLM are favourite at the moment while I contemplate The Rapid Models stuff!
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