FMS T28 Trojan v4.

[Colin Leighfield]

I bought this last year but just got around to trying it out. The wind at Fradley today was varying in strength and swinging between along and straight across the runway. Not ideal for a first flight but having mused on it for a while with Dave Wright we decided to have a go and Dave being far better than me agreed to do the maiden. It really flew well and didn’t need a lot of trimming . I had a go on the second flight. However while getting ready for the third flight the nosewheel retracted and wouldn’t come back down. The mainwheels continued to function normally. Because the doors are closed I can’t access the leg and servo without breaking something and the access from inside is insufficient. I will persevere but if anyone has any ideas please let me know!

[Ron Gray]

Have you tried to operate the nose wheel servo directly using a servo tester?

[Colin Leighfield]

Thank you Ron, Dave suggested that but I am ashamed to admit I don’t have one! I’ll try and do something about it tomorrow.

[Colin Leighfield]

I bought a servo tester today and while trying to understand the Chinese English instructions tried the plane and the nosewheel leg started to work again! After a few cycles though it started to make squealing noises and then failed again in the closed position! Clearly there is a fault with the retract unit, somewhat galling after only two flights with perfectly good landings on a smooth runway.

I managed to locate a replacement online with Wheelspin Models and ordered it, but it won’t be in time for the Fradley Scale Day on Sunday. Having to shell out nearly £50 isn’t much of a joke, I hope the replacement is satisfactory, otherwise I am very pleased with the plane so far but there are limits! My first experience with FMS.

[David Ashby - Moderator]

Colin, I had the same trouble with an Edf Jet from FMS recently. The nose leg was cycling as I flew around, luckily it decided to stay down long enough to land. I wondered if plugging the nose leg retract directly into the RX might help and it did, problem solved.

So, if you have a spare receiver channel try doing that. I got the impression that the three-way y lead into which the retracts connect was the problem and the nose leg wasn’t getting the power it needed prompting it to behave erratically,

[Colin Leighfield]

Hi David. Thank you, that is a very helpful suggestion. It does use these multi-connectors designed to make life easier and it is true that before I tried it yesterday I had unplugged and replugged the servo! I will have another look this morning and do exactly what you suggest.

[Ron Gray]

That’s what I’ve done with my Freewing Venom, the sequencer packed up so I’ve wired direct to the Rx and programmed the channels with delays / slow so that doors can open and gear can operate. No such problem with the Trojan as the dorms are wire operated. One thing to watch out for is the nose wheel leg, the joint between the oleo and the plastic nose wheel support is ok for smooth surfaces but not too good for bumpy grass fields.

Colin - you didn’t need to order the full nose wheel set, you could have bought just the retract unit for approx £16. But if you only want the retract unit, pm me about the leg!

Edited By Ron Gray on 19/07/2019 09:16:46

[Colin Leighfield]

Ron, thank you for that also. I realised that I could buy the retract unit on its own but bit the bullet and bought the lot to ensure spares for other events! Often when you need these things you can’t get them! I take your point about the risk of damage on bumpy surfaces and at least I will have the bits if (when) something happens. Later on I will try the direct connection method and see if that gets it working, watch this space!

[John Lee]

Thanks for the tip David, I've not had a problem, but this morning I've done as you have suggested with my FMS Hawk.

The T28 just seems to be the perfect layout for fine flying models. I've never flown a bad one, from the micro indoor to giant scale. I presently have the 1.2meter & 2 metre E-flite versions. They go well with a very solid 'sit' in the air and are definite keepers.

[Colin Leighfield]

I took the servo plug off the connection board and plugged it into the rx, replacing the existing one that goes into the board. Result was that only the nose leg worked, meaning I need to also disconnect the main gear servos from the board and connect all three together through a Y-lead. I’ll try and find one. However, when I put everything back it all worked normally again, so clearly there are connection issues here. However, the disconcerting thing is that at the end of retraction there is for a second or so a “ motor over-run” sort of noise from the retract unit that wasn’t there originally, so something isn’t right.

Here are the weaknesses of on-line purchasing from distant sources and the problems that exist as soon as you have flown the model in terms of resolving issues and getting dodgy parts replaced without shelling out, particularly if you just want to get on and fly the thing. I will simply keep my fingers crossed for tomorrow and fit the replacement unit when it arrives next week.

Edited By Colin Leighfield on 20/07/2019 07:48:12

[Colin Leighfield]

I took the Trojan to Fradley Scale Day today and the undercarriage worked reliably. It flies really well and the flaps even on position one slow it down remarkably, I used that position for landing, it just greases in very smoothly. One point of uncertainty was the LiPo specification. I was surprised that the recommendation with the plane is 4S 2600mah, which seemed conservative. Therefore I am using 2900 mah, although it is clear from YouTube that 3600 appears to be the right choice. Therefore I am limiting flight time to five minutes for now. However because son James flew it so well when I handed it over to him I got distracted until he called loss of power on a low fly-by and I realised that it had been going for nearly eight minutes! I panicked and shouted to get the wheels down, he cool headedly ignored me, turned slightly away from the runway and did a greaser belly landing on the grass, not a mark! here is the video, like so many the first part is distant specs after the take-off, but later it comes in closer. Co-incidentally Chris Walker was flying his beautiful Bryan Taylor Texan at the same time and you can see this as well. More interesting because the T28 was designed to replace the T6, so there is a proper relationship. Jet enthusiast Dick was flying his very fast Mig 17 and this whizzes by as well

Edited By Colin Leighfield on 21/07/2019 20:07:01

[Colin Leighfield]

If anyone had looked for the video and found it was not available it was because I had left the YouTube setting at “private” not public. I have re-set it so it is working now. Not very good because of my lack of skill, but might be worth a glance for those interested in the plane.

[Chris Freeman 3]

I bought one second hand a few years ago and still fly it. Great flying aircraft and very scale like in the air. The retracts have never let me down but I do wonder about them at times. I look at this aircraft with the lights, gear doors and working cowl flaps and wonder why I even bother to build a scale plane as this has more working detail. I do like building though and will continue to try match this one.

I enjoyed my last flying session so much with this aircraft that it cost me quite a bit of cash as I bought a bigger brother, A YT/ ESM T 28 with a DLE 55 ready to fly.

[Chris Freeman 3]

I do wonder how the radio manages to work with all these leads and servos, retracts and sequences for the doors.

[Colin Leighfield]

Thanks Chris, everyone speaks well of all the models of this plane. The FMS v4 version has some differences to the V3. They have taken away the working cowl flaps, they are now fixed. Also the retracts are now all sprung oleos, they seem to work well. The gear doors are simply operated with a plastic bridge that is connected with wire to them. They are lightly spring loaded in the open position and pushed closed by the nose leg bearing on the bridge as it goes to the retract position. There is no sequencer. So it uses six channels, motor, ailerons, elevator, rudder, retracts and flaps. My retractable nose leg seems to be working normally now, I’ll see how long that lasts!

I can well imagine that your YT version with DLE55 is great to fly.