Ever wanted to get into or improve your aerobatics?

[john melia 1]

Whats the consensus on the wire undercarriage , and has anyone flown one of these with either a petrol or nitro motor

["L"Plate]

Geoff,

The problem with “Z” bends apart from the fact it has a radius in the bends that can bind or wear the hole, it the fact that to allow the “Z” to be fitted the section that goes through the horn or arm is wider than then needed, this allows the control rod to move up and down causing play; further as the wire is thin and the force is applied to one side, it will flex (unlike a clevis or ball link that transmits the force straight along the rod, a good reason not to put any bends into the rods to get around things), loosing the positive control movement needed (allowing the surface to be blown back and in extreme cases even flutter). To get a “Z” bend through a fibreglass horn the hole has to be enlarged to larger than the wire diameter and this also leads to slop, you can get away with it with nylon horns as they stretch / flex a bit.

I think Peter thought I was talking in general about the grommets and made the same mistake I did reference the size of you model, as I said on a model of your size and with ring grommets I would direct fit but larger models with full width or double grommets I would always use them to isolate the servos from vibration.

John,

That is a hard question to answer, it is down to the quality if the wire, the weight of the model and the standard of the field (and the pilots landings). Some of the wire UC’s I have had in recent times, supplied with kits, are just too soft and bend; in the past I have had some wire so hard that it has broken. The alternative is of cause F/G but again some of these can be brittle or delaminate, I prefer F/G for heavy models off grass. There is an argument (which is valid), that if the UC is too stiff the shock of a less than perfect landing / rough field, will be directly transmitted to the airframe and could cause damage that is unseen or ripping out the lower fuselage (unlike the soft legs absorbing the shock by bending).

Sorry for the none answer.

[Geoff Reynolds]

Thanks 'L' Plate, I'm getting the picture. I'll have a look on't'interweb thingy and see what's out there. How big? 2mm, something like that?

Re John Melia 1's query.

I was told by Peter to beef mine up a bit as it may be a little weak. However, Chris Bond says that it should be perfectly adequate as it is. So all I've done is wicked some extra cyano around the mounting plate area and all joints and will see.

Cheers

EG

["L"Plate]

Hi Geoff,

For a model of you size a 2mm threaded rod cut to length should be fine, if you wanted to go the extra bit to stiffen them up, you can sleeve it with a piece of carbon tube with an internal diameter of 2mm. I have a few model set up like that and it works well.

Good suggestion to wick thin cyno around the mounting plates and into locating holes post one of the link explains and it works for UC's as well  http://www.rcmodelforum.com/showthread.php/226-Servo-fitting

As you may gather I post my builds on that forum, with tips and explanations of what I am doing and why. A tip for your hinges may be worth a look at  http://www.rcmodelforum.com/showthread.php/227-Fitting-Cyno-Hinges

With F/G UC's that are bolted to the bottom of the fuselage, some pilots fit them with nylon bolt that can shear in the event of a heavy landing saving the fuselage and legs. On your model I would probably start off without the spats and some bigger wheels, if you fly off grass (spats and small wheels on grass at this time of year can be a big problem, even on bigger models).

Edited By "L"Plate on 19/01/2015 15:25:21

[Peter Jenkins]

John - not sure which version of the Monolog you are referring to in your post above. I've just got a second hand but unflown Monolog 70 but have yet to fly it. I understand that the wire undercarriage is preferred by the manufacturer but they provide a fibre glass (or carbon - not sure which ) u/c as well. I understand the issue with the composite u/c is that it provided lift and so gives you yet another variable (since lift is dependent on airspeed) to consider when trimming the model. Hence, the manufacturer's preference for the wire undercarriage on the Monolog 70. Once I've flown the 70, I'll post my views on it here as it seems at first sight to be an excellent way of starting out. It can be either glow or electric powered which is an increasing rarity these days in specialist aerobatic airframes.

Having said that, all my 2 mtr airframes have had carbon undercarriages so the issue about the u/c providing lift/drag applies to these airframes as well. I have not had any issues (other than with my fingers controlling the sticks!) with this undercarriage arrangement.

What is an issue is that to get the vertical performance, F3A airframes are built light and you are assumed to be able to land your aircraft like a feather! Every now and then, things don't quite work out like that. I'm just in the process of repairing my current F3A following the undercarriage plate pulling out when I misjudged a landing in a 90 deg cross wind. OK, I shouldn't have been such a twit but if you never practice this when you face it in competition you will be at a disadvantage - at least, that's my view! So, it pays to put a little bit of either carbon cloth or tows around the undercarriage mounting to give that little extra protection for the odd bouncy landing! Don't go over the top though as you'll end up piling on the weight!

Peter

["L"Plate]

On my Monolog 110, which can run any conventional power train: electric, nitro or petrol; I have the wire UC and can say it is a bit soft (and my landings are not that hard normally) but no structural problems. As Peter said, according to the manufacture there are some aerodynamic issues with the G/F legs, especially in knife-edge flight.

I didn’t know John had a Monolog

[Martyn K]

Dundee MAC have this useful section on Flying Aerobatics with some lovely diagrams that some here may find very useful.

Martyn

[Geoff Reynolds]

Posted by "L"Plate on 19/01/2015 15:24:35:

Hi Geoff,

For a model of you size a 2mm threaded rod cut to length should be fine, if you wanted to go the extra bit to stiffen them up, you can sleeve it with a piece of carbon tube with an internal diameter of 2mm. I have a few model set up like that and it works well.

Good suggestion to wick thin cyno around the mounting plates and into locating holes post one of the link explains and it works for UC's as well http://www.rcmodelforum.com/showthread.php/226-Servo-fitting

As you may gather I post my builds on that forum, with tips and explanations of what I am doing and why. A tip for your hinges may be worth a look at http://www.rcmodelforum.com/showthread.php/227-Fitting-Cyno-Hinges

With F/G UC's that are bolted to the bottom of the fuselage, some pilots fit them with nylon bolt that can shear in the event of a heavy landing saving the fuselage and legs. On your model I would probably start off without the spats and some bigger wheels, if you fly off grass (spats and small wheels on grass at this time of year can be a big problem, even on bigger models).

Edited By "L"Plate on 19/01/2015 15:25:21

OK,

I'm decided I'll fit ball joints one end and adjustable clevis the other.

I've got snakes and carbon rods supplied with my kit, the snakes are pre installed and I've threaded the carbon rods through.

Have used cyano and shrink tubing to bond threaded rod to ends of carbon rod before (once) and I think this is the way I'll go again, but with the clevis adjustment if I'm not accurate enough.

I've pretty good faith in my landings and our field is close mown grass usually, so will give what I have a go. They should rip out OK as only thin fibre tabs with short self tapers for connection to underside in slot.

WOW, what a learning curve this all is from foamie buy and fly!!!

Grateful thanks for all the help coming in.

EG

[Geoff Reynolds]

Also must add it is great to see RCM & E doing a feature on F3A in the latest mag.

AND all those F3A models fairly flooding onto the market recently.

Ashley H and the boys at GBR/CAA must be pleased to see the increased interest being shown in the sport.

EG

[Peter Jenkins]

I had the opportunity to buy an unflown Monolog 70 recently. There wasn't much needed to complete the build but the weather hasn't been conducive to maiden it till recently. For the record, the Monolog 70 details are as follows:

• 1500 mm span and 1800 mm length
• will take a 50 2 stroke, 70 4 stroke or an electric motor - mine has an AXi 4120/20 with a Castle Creations Phoenix ICE 75 ESC and I'm using a 5S 5000 mah drive battery cos I have a few of them. You can also use a 6S
• Construction is wood and flim covering.
• Undercarriage is the substantial wire torsion bar set up.
• You need 4 standard servos - you can go digital if you want but they are not needed
• AUW is 2,500 gms with battery if flying electric

Bondaero have these at £135, although apparently currently out of stock. That's a fantastic price for this aircraft especially since you can just drop a 46/50 2 stroke into it and use your existing servos. Having said that, I'd put an Irvine 53 on a throttle pipe on this to get the sort of vertical performance that will make flying aerobatic manoeuvres effortless. As I said, my verson came with an electric setup. If you want to try electric on a budget, then you will be able to kit this out with a 1,000 watt motor and 75/80 amp ESC from the web for around £50. You'll also need drive batteries and a 5S 4500 mah will probably set you back between £25 to £35. Of course, you'll also need a charger than is man enough to charge a big battery like that.  Alternatively, if you currently use 2200 3S packs, just connect them up in series to get a 6S pack and away you go!

First flight was completely uneventful and I had a first. There was no need to apply any aileron trim to get the aircraft to fly with wings level - says something about how accurately the wings were built and how accurately they are jigged to the fuselage. Some elevator trim was required as my battery pack is bigger than the recommended 4500 mah. On the other hand, my pack is good for well over 12 minutes and will probably reach 15 so allowing 2 B schedules to be flown per flight. It managed the GBR/CAA Masters schedule without difficulty so it's a pretty good design.

Talking of B's, this is a great aircraft to tackle the B with. Provided you have it set up correctly, you will find that all the manoeuvres are so much easier to fly than a non specialist F3A design. More when I've flown it some more.

Edited By Peter Jenkins on 29/01/2015 19:50:17

[Peter Jenkins]

Well, I managed to get out and fly the Monolog 70 with a 6S pack today. I can now tell you that it will fly the FAI P15 schedule with ease! So, if you are able to get your hands on one of these then you will have an airframe that can be used for getting your B and then flying all the schedules (Clubman, Intermediate, Masters) up to FAI P15. It is truly a delight to fly.

I used a 4000 mah pack and my battery checker indicated there was 36% of charge remaining after the flight.

Flight time is a comfortable 14 minutes when flying schedules so longer if you are just pootling around.

The bad news is that Bondaero have no other shipments coming in but... Hobby King seem to have an aerobat called the Ionos which looks suspiciously like the Monolog and is now priced at £156.67. The description says it's for electric power only though. However, if it is the Monolog design, I guess it should be able to take an IC engine.

[graeme jones]

Peter - they do look similar don't they? There are differences though, which can be seen by comparing the pics on the two sites, and the Ionos is heavier by about the weight of the battery. It's now on sale from the HK UK warehouse though, at £145.48. No reviews yet and it's in stock so they may not have sold many.

Hope to see you at one of the comps. this year.

Graeme

[Gordon Brown]

Peter - I clearly need to get up to Bury or Knettishall with you, I also have a Monolog 70, bought second hand at the Nats, but I've had problems trimming it as there seems to be some weird coupling going on, especially in rolls. As yet my flying isn't up to scratch but it looks like this model should take me well beyond my level of incompetence!

Gordon

[Peter Jenkins]

Look forward to it Gordon. Have sent you an email.

[Peter Jenkins]

Hi Graeme, I've had a PM to say that they are the same. I guess the only way to find out is to put them side by side. Hope your field allows you to get in some practice and look forward to seeing you at a comp this year.

Peter

[Peter Jenkins]

I have just announced that I will be running an NPOD at the Raydon club near Ipswich here. If you would like to take part please go to that thread and respond from there so that we keep this thread clear.

Peter

[SR 71]

Hi Peter im currently looking at getting a model to practise f3a and i like the look and sound of the CPLR GALACYIK but im wondering if its on the small side @1500mm wing span,

I want to get it right as at £399 for the airframe its not cheap , ( for this pensioner )

[Gary Manuel]

Hi SR71,

Have you thought about the CPLR Axiome 70? I believe that it's the predecessor to the CPLR Galactik.

It's a very nice practice plane and can be found at reduced prices at the moment, such as HERE

[Gordon Brown]

SR71, you should consider the Sebart Angel 50, which is available from Kings Lynn Models for £213 airframe only. My son flies one, as Peter well knows, and it's probably just about perfect for anyone entering F3A. Nat won the NPOD and the Warboys Clubman class last year with it. 4Max do a very good motor for the Angel and you could probably put one together ready to fly for about £400.

Gordon

["L"Plate]

Hi SR71,

I can recommend a look at Bondaero http://www.bondaero.co.uk/ I have had very good service from him, 2 Monolog 110 (crashed the first one after hitting a bird at low level half way through a roll), and I am now building the BiSIde 70. He has a secition for Sport and Practice Airframes and currently has the Axiome 70 (CPLR) model on special offer. You will find alternative motor on 4Max and ESC at Hobby King, fit good quality servos and any of those models will be a winner, capable of taking you up to and including Masters. Peter has a Monolog 70 and it sounds like it performs as well as the 110. You will find that the 70 size model's fuselage are not small and these models do perform very well.

[Peter Jenkins]

Hi SR71, you've already had significant input on your question. I would say that a 1500 mm wingspan is not an issue basing it on my experience with the Monolog 70 that also has a 1500 mm span. As I say in my post above, with a 6S I could fly the FAI P schedule and the model handled it with no problems. I'm assuming that you are looking at the Bondaero site for the Galactik. The link I've sent you, if you have not already seen it, lists his smaller offerings and he's showing the Galactik 90 at £359.10. The Axiome 70, which has had some very good reviews, is reduced to £225 and, if he's still getting stock, the Monolog 70 is a real bargain at £179.99. Bondaero is also showing the Nuance 70, with a composite fuselage, at £309. The Nuance 120 flys beautifully so I would expect the Nuance 70 to be up there as well, The only thing to bear in mind is that repairing a composite fuselage is a little more ticklish than a wooden one unless you are used to working with composites.

Gordon mentioned the SebArt Angel which is also an excellent flying model - I do know that Angel production has stopped but Kings Lynn are still showing it at £213. I think the Hobby King Ionos is another possibility as I believe that it's really a Monolog 70 and that's around £195.

Bottom line, none of the above models will disappoint you. I think the Galactik and Axiome may have an edge when flying combined rolling and pitching manoeuvres, such as rolling circles, but then again you would have to be a very good pilot to notice the difference.

Good luck with whichever one you opt for. One thing to consider is that the B J Craft kits (the Bondaero offerings) come in wooden boxes so are very well protected in transit.

[Geoff Reynolds]

Hi Everyone,

I finally maidened my Monolog 400 yesterday and, unsurprisingly to many of you I'm sure, it flew fantastically from the off. Just a couple of right clicks on aileron and a couple of down clicks on elevator had it flying very smoothly, hands off.

Might be a touch nose heavy, I've yet to get the battery position just right, but a good starting point.

1. The meter showed that it was running at a steady 280 watts, pulling 22.2A on a 12 X 6 prop. Motor is a Turnigy Aerodrive SK3 3542 800kv with an 80 amp ESC (way over the top).
2. Three six minutes flights left (according to my battery checker) 32%, 31% and 30% in the 2200mAh batteries used.
3. On re-charge, the three batteries took, 1104mAh, 1187mAh and 1249mAh, which is about 50 - 43% usage. So a very efficient set up, or is it?

Could my checker be wrong on all or some of these readings and should I get another, mis-trusting everything it says?

Many thanks to all who have provided help through this most protracted build and kit out. The wait has been worth it for me, I've never flown anything so dialled in from first take-off.

Now on to the trimming and getting ready for a shot at a competition before the year is out.

'B' test first, tomorrow the world!

Cheers

EG

[Geoff Reynolds]

Well, that has to be the shortest period I’ve ever flown a new plane. Three Friday, two and a bit today! The Monolog crashed this afternoon and is in a pretty bad way.

Damaged and crushed cowl, considerable front end breakages forward of wing roots, motor hanging out, damage all along the fuselage to just behind cockpit, where it is a little banana shaped. Cockpit is damaged at rear edge. The tail end is still structurally sound. Wings intact, but have torn out of the fuselage on starboard side.

It was being piloted by one of our club instructor/examiners (and renowned model aerobatic pilot) to check it out re trim, as I still thought it was a tad nose heavy, despite battery movement, which he confirmed.

About halfway through the flight (as judged by timer,) he became quiet, before uttering “This isn’t looking so good” and the plane began diving towards the ground. He managed to regain control at about 12 ft, but the plane was oscillating violently from right to left and back again, almost inverting at times, and he couldn’t get throttle control.

He did remarkably well to slowly bring it lower and slower, but still oscillating wildly, until the inevitable happened and it nosed in, cartwheeling to a stop in a cloud of dust maybe some 50 yds into an adjacent field.

When we arrived at the crash site, it was sat on its wheels, cockpit off, motor hanging out, but all control surfaces worked correctly.

BUT the receiver(s) Spektrum AR 6200 were flashing, as though not fully bound. They had been fine when I put the cockpit on. The battery tested fine at 11.6v and indicated 57% capacity (only taking 852 mAh to top up eventually).

Despite trying to replicate this by disconnecting and reconnecting battery and by turning off and on the transmitter, we couldn’t make the lights blink. It just un-bound and then re-bound.

At a loss to explain further at the moment, but would hazard some electrical/radio problem that we can’t replicate.

Not sure if it can be saved and was the last of its kind I believe.

Devastated.

Pride definitely came before this fall!!!!

[Peter Jenkins]

Hi Geoff

Congratulations on getting your Monolog 400 into the air. I think that most pilots who have never flown a purpose built pattern aerobatic aircraft are taken aback at how well they fly.

To answer your specific question, the only real answer to how much your flight took out of the pack is how much the charger puts back in. Most of the capacity measurement devices are inaccurate to some extent and really only give you a proper answer to "is the pack full?"

The other point is that it depends on what type of flying you are doing. If you fly a Clubman schedule it will probably take more out of your pack than if you fly a B schedule although with the B there is a lot of flying round the circuit to do between manoeuvres so not hard on a pack.

With the Monolog 70 using a 6S 4000 mah pack. I can fly the FAI P schedule - takes around 7.5 mins and will have used up 60% of the pack. I can fly a B schedule and fly a couple of additional minutes of aerobatics and land after 12 mins with 60% of the pack remaining. With a 2 mtr machine, it takes around 7.5 - 8 mins to fly an FAI P schedule and that will leave between 30% (calm conditions) and 10% (windy conditions) remaining in a 10S 5000 mah pack.

Peter

[Peter Jenkins]

Oh Dear! We cross posted. So sorry to hear the bad news.

Peter