Trex 700 gas conversion

Helibug

Thought it might be of interest !

Oh Yes!

With the cost of the conversion plus the cost of the engine, say from here http://www.rossmod.co.uk/store.php?search=1&value=188&page=2 Looks like the total would run to more than £450 . Thats a lot of glow fuel!!!

Yes indeedy!!!

based on this years fuel cost, it will take two years to get even !
I used over 3 boxes of 20% nitro (4 gallons each box at 5 ltrs, cost per a gallon is £18 ish)
The advantages is that they are a lot easier to look after, and more importantly you get more flight time per a tank ! so I have been told !!!

I want to see your calculations up to the break even point as I can't ever see a helicopter lasting long enough to break even

Same here. Don't forget it's the diference in cost per minute flown between glow fuel cost/m and petrol fuel cost/m. I'll no doubt get corrected. But, I believe you would use approx half the amount of petrol versus glow fuel per unit time flown at a 1/3rd the cost per unit of fuel used (petroloil @ £6.00/g; glow @£18.00/g). So, for every gallon of petroloil fuel used would save you £12.00 approx.
Therefore, £450 divided by £12 equals 37.5 gallons approx. You would have to use, very roughly, 37.5 gallons of petroloil to break even. Thus, multiply twice (because you will get twice as long for the same amount useing petroloil) the flying time obtained from using a gallon of glow fuel by 37.5 and you'll get a very very rough idea of how much flying time it would take. Submitted for correction, criticism and brickbats from the members

Zaidy is still working it all out then trying to get the scanner working to post his findings on here

Surely you would buy the kit without the nasty glow engine in though, thus meaning the cost of the conversion is just the helibug bits? The Petrol engines are about the same cost as the Glow ones right? Roughly? If that is the case, you can knock off £225 odd out of your cost breakdown straightaway....

Unless, of course, you already have bought the Glow engine....

Andy

But arent petrol engines bigger and heavier than the glow engines and you have to have a separate ignition system to!

I think another issue here is that you're converting pre-existing glow model, in this case the Align 700 which is built around the 91 glows and converting it with the necessary bits to a 23/26cc petrol. It would I think be far cheaper to build/buy a ground up petrol powered heli

Dave and Zaidy already have the glow motors I believe. They could accept the fuel costs until the motor requires replacement or sell it now as new or nearly new to defer the conversion costs. Lets say the 91 glow, doing lots of hovering and aero's, uses 1.6 fl.oz/min. 160 fl.oz.in a gallon, therefore 100min flying on glow or 200min (1/2 the consumption of glow) on petroloil per gallon. From previous post 37.5 gallons of petroloil required for break-even point. Thus, 37.5 * 200 =7500min or 125Hr. total flying time. This would obviousely be less if the 91 glow was sold. How much less depends on price obtained for the 91 glow.

Therefore bringing into the equation the additional weight of the petrol conversion over the standard glow powered machine fuel consumption would be higher than originally calculated, thus making the conversion non cost effective, if however the petrol conversion did take place...........................

What if you couldn't sell the 91 glow engine & associated components after converting to petrol, this expense must also be incorporated into the overall cost effectivenss of the conversion, could you sell the 91 as new or used thus further reducing the overall benefits of the conversion in the first place.

Hey, hold on, my marker pens have dried up and the wipe board needs a bloody good clean! Can Andy take over now with a few equations perhaps to clarify the process

I've had enough now as well

What laughs and jolly japes we have on this forum, eh

Good effort lads, LOL

Its unlikely I will get a good price for my almost new glow engine, we all know that if its used, it will sell at half price !

Allan, I am still reading through your post regarding the calculations, Rich is correct, I am still trying to work in out


I will carry on flying my 700 hopfully for a great deal longer than Rich predicted although now its been said I have to be careful



Happy days and many thanks for the feed back guys


All the best for the new year to all..

Who is out flying on friday, weather is looking good

Now if we were to electrify said helicopter........................

No mark, no!

Mark Barnes wrote:Now if we were to electrify said helicopter........................

Battery cost, unless you get them from you know who ! But, everything is in short supply

I have enough trouble getting my 450 sorted never mind a glow to battery conversion NOOOOOOOOOOOOOOOOOOO

I doubt that I will fly on friday, to much celbrating and all, ya know!
Mind you I do want to have a 'Flying start' to the new year!

I guess that my vapor will have to do!

All we need is a bloody big electric motor and a looong set of pantograph pick-ups supported by helium ballons, only fly directly under power lines and we're away (possibly with the fairies )

Convert it to petrol first then do the calcs then convert to leccy "if you must"

Brian Colclough wrote:Convert it to petrol first then do the calcs then convert to leccy "if you must"

now why didn't i think of that..... Cheers Brian