Hi All,
First time building Jet turbine plane, The model is 100% completed currently waiting to be MOP and maiden. I can not sleep since, and won't be till she's mop and airborne, there are always been questions at the back of my mind, and one questiion standout is "Will it be problem if there is no servo wire insulation?"

Can some one please put me out of my miserable, and put my mind to rest.

I have had built several heli's and gas planes, good insulation on servo wires are a must since vibration is extreme, while building my first jet, my assumption is that jet do not produce vibration. Is my assumption fair and accurate?

Accurate, vibration is not an issue, at least I have not experienced that in my 12 years of turbines.

your assuption is fair and accurate. Turbines do not produce vibrations. When they do vibrate? Thats how you know when it is time to send it in for service.


Welcome to the jet community, Have a blast and good luck with your maiden flight.

Mark

Thanks Mark and RCAND.

regards
Pat.</p>

It's not clear exactly what you mean by "no servo wire insulation". While vibration is not a concern like it is in gasoline powered planes, you still need to secure the wiring. Wiring can flop around due to airflow through the fuse and during airplane maneuvers. You need to make sure any wiring near the air inlets and turbine intake is secure so that it can't get sucked in. Rubbing and chafing of wires can be an issue. Any wiring near the engine tailcone and tailpipe need to be insulated from the heat.

Joe

i use fiberglass sheeve for the area around turbine/bellmouth and then aluminum/heat blanket for the rest.

Nice Hawk! I have to ask you what the acronym 'MOP' is... I never heard of that one.

certifications for the down under guys.

Hi All,

I think the MOP is acronym for "Model Over Permitted". Down here, to fly any model above 7kg, the model must be inspected and given a certification to fly.

'MOP' stands for 'manual of procedures'.

http://www.maaa.asn.au/maaa/mop.html

The MAAA (our AMA) has lots of different rules & procedures one of them being inspection & certification of models over 7kg & another being for inspection & certification of gas turbine powered models.

For both of these the model has to be considered airworthy & built to the rules PLUS the pilot must be able to fly & operate the model safely. We don't have turbine 'waivers' here.

When a guy say's his model is going to be 'MOP'd" he means inspected & certified. It's nothing to do with buckets or detergent!


What do you mean by servo wire insulation? Turbines have no vibration if running properly. The wiring to tail mounted servos is often sleeved in heatproof tubing to protect them from heat given off by the tailpipe.

Fibreglass sleeving is readily available from electrical wholesalers like TLE, JR Turk, Lawrence & Hanson etc. Lots of sizes available, the larger sizes will easily fit a servo extension lead without taking off the plug. - John.

Whilst turbine models don't usually suffer from vibration, it's still good practice to add another wrap of "something" eg self amalgamated tape where servo bundles are scured to cable tie pads, or especially the aluminium sticky grips.

So called "heavy duty" servo extension wire seems to have very soft insulation, and very little copper in it !
I prefer to use Alpha wire, PVC irradiated 24 awg minimum. It's got a thin insulation that is VERY tough, yet still quite flexible.

http://knol.google.com/k/wire-guy/ir...kca96nb0mp/11#