Andy J

Thought I had seen one on the MR site could not spot it when I looked as went to the accessories page a couple of days ago. Do you find it does any damage to the prop nut Mike? Its all a bit bizarre regarding the starter. Fitted a three inch spinner yesterday and the cheap and tatty 12v starter easily started the engine on a 11.2V 5000mah lipo. Tried the larger geared starter from JE using the same battery and it would not even get the prop passed TDC. Not at all sure what voltage is the JE starter should run on as unsure which of the two types he sells as I purchased it was some years ago. Even looked last night for a 4S lipo to see if I can speed it up, but given a lipo will be at least £60 think I will just stick to my cheap and tatty 12v job.

May need a light sand to improve the surface prior to re-paint.

This may need some work to make it fly again.

Well the NGH GF38 does fit within the cowl of a Flair TM. Does need a custom exhaust though. Just being doing further ground runs on my installation a couple of hours ago..

What is the pop up needle Paul?

Andy, the concept of dog teeth to contact the prop could be a possible option but I would be concerned of possible contact with the cowl. Must have an old spinner in the spares box so will fit that whilst I await the one from overseas. Once the engine gets ran in hopefully it will be more easily turned over and started by hand. I also fitted a new carb pump diaghram a couple of days ago which I hope will have improved the engine priming with the choke closed.

Did not spot those yesterday when I went looking for anything model related. Still always worth looking periodically as the box of assorted heat shrink which I purchased last year is still proving useful. Did see a 12v rotary tool though if anyone is looking for a cheap Dremel look-alike.

Thanks for the responses. Certainly was not aware of the BMFA rules about fitting spinners. Actually do have a spinner on order for this particular engine installation but had to resort to ordering one from the far east as there seems to be a shortage of 2.25inch diameter aluminium spinners in the UK at the moment. Certainly would be concerned about the potential for loosening the prop nut as the engine does have a tendency to keep throwing the prop when it backfires, so using a socket drive is obviously not the way to go to overcome the issue of turning the engine over with one of my starters due to the lack of friction between the starter cone and the prop nut.

Is there any issues using a socket driver to engage with the prop nut to start a larger engine as find it near impossible to get a decent contact interface between the engine prop nut and the starter cone? Will of course include an inline ratchet drive to allow removal of the socket once the engine starts. Little lost as how to couple the inline ratchet to the starter but sure I can think of something.

Mike is there any connection between the NFL issue and uncontrolled servo demands which was an issue some years ago? The reason I ask is that on the first flight after I had purchased the Horus X10S which was just before they went obsolete is that I swore I had an uncontrolled elevator pitch down demand which was proceeded by a loss of telemetry warning. Luckily the model was only about 6ft from the ground on a landing approach so little damage was done. Given this issue I changed my Tx RF Sw to avoid the problem and have not had any further issues other than loss of telemetry alarms on a glider which I suspect was due to voltage drops caused by the motor being operated.

Think from inspection of the log the actual model started its short taxi and take off run at around time 13:31:31. Impact was at around 13:34:09 when I let go of the up elevator demand. Tx was turned off at 13:34:24. Rudder is indeed on the aileron channel. Nothing came adrift in the fuselage to change the cog position. The only damage was to the outer dihedral breaks on both sides of the wing with the rear section ribs around that area completely destroyed. Main spar and LE remained attached though.

Yes the Rx stayed powered Mike.

Rx is a Rx6R. Just checked if I had anything in the Tx to programme a 6R but found nothing. Note I did download the file FW-RX4R-RX6R-c2.1.1 back in Sept 2020 on my PC but that does not stack up with versions listed on the FRSKy site for the Rx.

Was using the Tx to test the aileron connections on a model and did notice the Tx voltage was only showing 2 bars out of 4 but don't think the Tx voltage is an issue, but it is strange that it increases from 7.5 to 7.6V in the log file. Anyone know what A2(V) is?

Agree with all of the above as I have now purchased upwards of 6 or 7 engines from ebay over the last 5 years. A good 50% would have best described as dogs dinners and have needed a minimum of a bearing change. Still I keep purchasing engines in this manner, so obviously I am not learning from the experience. As Nigel states at least you do get some protection through PayPal and Ebay.

It was the application of full up elevator had no effect. Assume throttle closed but cant be sure as the motor is very quiet and I am part deaf. Time is in hours, minutes, seconds. Flight was probably a bit shorter as the time starts prior to engine start. Think you can ignore Alt as the Rx does not have a pressure sensor.

Certainly was not a failsafe issue, nor a clevis issue. Could well have been a phone interference but would that have not been shown up on the telemetry feed? Certainly there are no incoming calls that day on the phone log. But as we all know the phone does periodically transmit data to the world and it could have been a message transmission. Could the failure of the outer dihedral ribs which resulted in the TE joint be an issue? Think this as unlikely as it would have resulted in a spiral and don't think the model turned in the dive of death.

Nope, fail safe operates as intended with elevator and rudder returning to neutral on loss of signal. Surprised no one has mentioned the mobile phone in my trouser pocket being an issue.

Well its not a fail safe issue. Throttle goes to low and elevator and rudder stay at neutral. Will do a further check just to see if the elevator stays at the last commanded position.

will check fail.

Dug the battery out today just to check what is was and it is indeed a 4 cell 2500mah pack. Turned on the power and telemetry read 5.3V fore the battery volts which fell to 5.1v as I put resistance on the elevator servo arm. Found it impossible to stop the servo moving so don't think it is a dodgy servo or voltage issue.

Thanks for the comments / queries. May have been confused regrading the battery voltage as it is possible that the battery is a 4.8V pack. Don't think I can dig it out of the model to verify as this will require major surgery. The loss of telemetry at time 13:24:34 (and battery volts) is simply because I turned the Tx off and went to collect the model. As can be seen at 13:40:03 the telemetry recovers when I switch the Tx back on to check if the elevator still functioned which it did. What is strange to me is what would have forced a stable high wing design into a vertical dive. Do notice that at 13:34:06 the battery volts are dropping as the elevator demands go towards full up and then recover as the model hits the earth at 13:34:11 and the elevator demand is removed when I realise all further control is in vain. Don't use a switch on this model as I simply just plug the battery into a floating servo lead connected to the Rx.

Mike Tx is 2.3.14-otx RF SW driver was upgraded when using the FRSKy OS to get rid of the un-commanded servo issues.

Looking for an armchair detective to suggest a possible reason for a loss of control which occurred yesterday. Model was an old school, high wing 3 channel Playboy with an ~90inch poly dihedral wing. Model was powered by an OS30 2 stroke and it had flown previously without incident about a week ago. Radio, FRSky Horus X10S with OpenTx software, 6 channel Rx fed from a 6v nimh battery connected directly to the Rx. Battery had been fully charged approx 1hr prior to the flight. So once in the air on its first flight of the afternoon the model was happily stooging around at approx 100ft at no great distance from the Tx for several minutes. Rudder was slightly twitchy but otherwise the model was fully under control. Then without warning the model twitched and then immediately entered a vertical dive. At this point the throttle was closed and full up elevator was applied which appeared to have zero effect. After impact with mother earth I turned off the Tx and recovered the model. Model was implanted in soft earth in a vertical orientation such that the motor was fully buried. Surprisingly the fuselage suffered little damage although the undercarriage was torn off and the prop blades shattered. The wing which where adjacent to the impact point had suffered the most damage with the outer dihedral ribs on both sides having disintegrated which allowed the TE joint to also fail. LE and main spar joints appeared largely intact. On recovery back at the car the TX was again switched on and certainly the elevator functioned correctly. Did have my mobile phone in my trouser pocket and the Tx antenna was I think in a horizontal attitude. So can anyone explain what may have caused this lack of control and what could have been the reason for a vertical dive? Attached is the telemetry log to see if anyone can spot any anomalous behaviour. Crash occurred at or around 34:23. Playboy-2023-02-14.csv

Thanks for the tips ED, currently using Aspen fuel and I certainly find the engine runs far better on it than petrol and has less residue emitted out of the exhaust. Prop is wooden, think it was purchased from HK, so probably not the best quality. Certainly the prop throwing issue has occurred every time I have ran the engine, so did ponder briefly today if I could drill the crank shaft prop driver to accept a couple of M3 bolts. Did find the engine has less vibration now that I have fitted an NGK plug so that was positive item of advice from another thread specific to the engine. Sure I already have a spare carb kit so will do that change as the engine has certainly sat for at least two of three years since I last played with it. Despite not quite scale like for a TM, will get a spinner on order tonight to allow a better interface to the starter.