Jim Cattanach

I just bought a Viperjet. Ali will have to be easy on my pocket.



[quote]ORIGINAL: cairoman


Ali,

Will you be bringing a few of those babies to JP to sell over the counter? I know Jim would like to buy one, besides me.



Chris

Gordon W

Another 3 flights yesterday afternoon. To my annoyance the plug blew and needed changing for the second flight. The first plug had only lasted about 7 or 8 starts, so I hope that’s not par for the course.

So which is the best and most rugged glowplug? When I flew glow, I found that Enya No3's were indestructable and used them for many years. Anyone use them on turbines?

Five of our club members have now seen and heard the model go and breathed in the characteristic aroma, and given it a big thumbs up on all counts. They seem to be as enthusiastic as I am that there’s now going to be a turbine flying regularly at our field, something that hasn’t happened since the RAF quit Chivenor around 1995 taking their Hawks with them up to RAF Valley in Anglesey.

I’ve reduced the aileron deflection and the slower roll rate is much better for me, especially for hesitation rolls. It did seem to barrel somewhat in slow rolls and I suspect that it needs less aileron differential than recommended.

In knife-edge there’s a fair amount of adverse roll with rudder so I’ll be introducing a spot of rudder-aileron mixing and most likely some rudder-elevator mixing too. The model will climb in knife-edge. No measurement for rudder throw is suggested in the instructions BTW.

I also did an outside loop and a stall turn. I tried a rolling octagonal loop a couple of times but only got 1/2-way round before veering right off track. The latter needs a lot more practice.

On the final flight I performed a few rollers. The landings are so easy that when I get down to some serious trimming and control harmonisation, it’ll be convenient to do a take-off, check the adjustment in flight, and if it needs further change, plop it back down, adjust the programming with engine idling, and then blast off again. Whilst I suspect that I can lose some nose weight, I like to make changes one step at a time, and I will get the controls harmonised to my preference before attending to the noseweight.

I was flying it from tarmac today and it got off in a very short distance, probably less than 75ft, and the climbout was pretty steep, especially towards the end of the 3rd flight doing the rollers, when 1.1/2lb of juice had been used up.

I also test-flew a Pica Bucker Jungmeister for a clubmate. A nice change of pace and I’ll have to get on with my 27.5% scratch-built Jungmeister which I’ve been designing for a while, for 11S lipos and a big Hacker A60.

The pic shows Nano and me following the 3rd flight.

Gordon

Ali

My Feedback: (5)

Hi Chris
Yes of course we will be taking Nano's with us to Jet Power. Pre order is advised as it looks as if we have quite a few sold before we even get there this year.
In fact we are doing a special offer that with every Viper Jet that we sell we give a nano away free....
Look forward to seeing you cypriots, and scot in a few weeks time.
Regards Al

bluescoobydoo

my wren blows glow plugs on a regular basis as well not as bad as it used to be but i am still replacing them way to often, my first glow plug only last about the same time.
speak to wren about it they might be able to help.
but it is putting me off wren,s a bit for my next turbine

Duncan

cool does that offer include me

Jim Cattanach

Use the data terminal to reduce the glow plug power setting to the point where the gas will reliably ignite. If the setting is too high, you will blow glow plugs regularly.

Turbinac

Yes, Chris,
I'll have Nanos and so will Ali and we'll be flying one so you can see how good it is in the air!

polarit

I maidened mine today, and it flies like a *****cat, until one bangs the sticks, then it really comes alive.
(exept for the ***** that flared too early, and pancaked it from little over a meter height - yes me )

Gordon W

I was wondering about that. I'm too new at this to have investigated all that can be done with the data terminal. Presumably the data terminal menu is intuitive enough that all I do is cycle the parameters using the up/down buttons until a plug volts screen appears, then use the +/- buttons to reduce the voltage by a small amount.

Will I need to adjust the gas regulator at the same time? If the gas/air ratio is correct to begin with, presumably not.

Thanks

Gordon

Gordon W

I almost achieved that on my second flight yesterday. The wing-tip skids worked to perfection and the covering isn't marked. That's why on the 3rd flight I spent some time doing rollers so that I could study the landing characteristics.

Gordon

Turbinac

I was concerned by all the comments regarding the high amount of noseweight required.

So I took a stock Nano kit off the shelf, built it and installed all the full house radio and MW44 turbine in it. It came out at 11 lbs 13 ounces and required NO NOSE WEIGHT whatsoever.

I used a 7.2 v Lipo and a 5 cell NiMh 1750 AH, both tucked up in the compartment above the nose gear. The Dubro 50 ounce tank, and as usual Hanson Air trap, and full size servos all round. Old set of Springairs with Robart wheels and a nosewheel brake from Airpower. Not as heavy as the super retract sets with trailing links, but I'm getting round to those, The model can stand the extra weight no problem.

What are you guys doing that makes it need up to a POUND (unbelievable) of nose weight to get it to balance on the CG given in the manual?

av8rk

Alan,

My P-60 powered Nano with the standard JetCat 2500 ma lipo and 1400 ma 5 cell nicad in the nose required no nose weight to balance per the indicated C/G in the assembly manual.....

Richard

Jim Cattanach

Gordon. Just plug in the data terminal & switch on the Rx. Click through the various settings till you come to " glow plug power" & enter that function. It will give some two figure number, say 35. Reduce whatever figure it says by about 3 or 4 to say 31 ( in the example I give ). Try starting the turbine & if it starts ok you could lower it some more, or try it at that setting. If the turbine does not start , you will have to raise the number by 1 or 2 The idea is to get as low a number as will give reliable starts. The gas setting should not need changing.

cairoman

Please count me in for one, any colour scheme, they are all very nice. That Scott, we are trying to Cypriotise, but, darn...unsuccessful

Likewise, looking forward to seing you too. Dinner is on Jim

Chris

cairoman

Alan mate,

I know how good ALL of you Boomers fly,ever since the first one I got from Ali SNR in Finchley, back in 2002!!! I am sold on those, always

Ahrbella again this year?

Chris

H.Dale

My Feedback: (3)

Alan

I have a Wren MW54 Mark II in mine. I used standard servos, mounted the turbine as far as possible and tried to put as much of my electronics as far forward as possible. I have wire gear with no brakes. I haven't weighed it yet so I'm not sure of that. I have a 7.2v nimh and a 4.8v nicad in the nose. As you pointed out from the video it was tail heavy. I had to add 8 oz. for it to balance on the CG called for on the plans. I know the MW54 is heavier than the MW44. Is it heavier than the P60? Maybe that is why I had to add more weight. Have you tried one with a 54 yet?

Hal

polarit

Alan

two comments on this - it may help a lot, if i install retracts later, AND i balanced it VERY concervatively on the wingtube

somebody mentioned that sandor has a very good offer on the nano gears at jetpower, so ......

gruntled

Alan:

Do you spec the servo torque for each particular control surface?

Turbinac

Nano is light and of moderate speed for a jet, so I use a good digital 5 kilo servo for the elevator and any good quality servos of moderate torque (anything over 3 kilo) for all the others. It does no harm to use better servos than you need, for peace of mind and also you may want to use them later on, in faster or heavier jets! The weight saving on cheap or lower quality servos is false economy in a jet.

gruntled

Thanks Alan. I just placed my order with Patricia this morning. Woo hoo! I ordered the Navy scheme, but was torn between that and the red.

Do any of you have any experience with the BMS servos? I have used them in smaller EDFs before with decent results , but I am not sure if they are considered up to "jet standards"?

I also just received a set of the trailing link gear from Sandor at Digitec. They look good to me and he is offereing an extra 20% right now in conjunction with a show in Germany.

noahb

My Feedback: (67)

I would stick with named brand servos for ailerons and elevator. The rest i think you will be ok with. I have read really good reviews about the HD servos from Troy Built Models (I think that is the name of them).

I would go with futaba, JR, or Hitec for the ailerons and elevator. The rest you can put std. but dencent servos on. Troy Built Models sells the 7955 digital servo for like $89 which is dirt cheap for the servo. You can also find good used servos like the futaba 9451 mg servo for around 135-150 for 3 or 4 of them. this is what i used for my boomer and have had 0 issuse with them (knock on wood).

I just ran my boomer today with the new Rabbit. WOW! I clocked the speed in a 5-8mph head wind and the speed was 157mph. I don't want to push the boomer any more then that as I know they are tough but don't want to be bagging up pieces either.

The rabbit is one bad turbine! my dry weight is right at 15.5-16 lbs. with a bit more then half a fuel load, it pushes it straight up (not very fast, but unlimited). Awesome turbine.

You might try looking on RunRyder.com for servos for you aileron and elevator. I would stay away from any of the 56XX hitecs. Only 59XX or the 79XX series. Futaba 9451's or 9452's are good servos. JR makes an exellent servo, but over time the gear train develops slop and for the price the 7955 is very hard to beat.

gruntled

Thanks. I'll look into those.

BaldEagel

IMO the 7955 are way overkill on this airframe, use Hitec 5725 or 5925 on the main control surfaces and 5745 or 5945 on the flaps, metal geared and good centering, they can also be programmed for individual fail safe, center, end point and speed, I use the 59XX in my Elan without any problems so in the Nano they should be OK.

Mike

BaldEagel

Double post:

Mike

gruntled

Hey Mike:

I looked up the 5925 on Hitec's site and could not find them. Are they still being made?