Replies to This Discussion

Permalink Reply by Paul Bonasera on September 24, 2014 at 9:06pm

That depends on which pilot is more suitable for the CH750.

There are soooo! many out there to chose from it really is your preference.  Any that are from 100 to 150 HP.

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Permalink Reply by Jonathan Porter on September 25, 2014 at 12:34am

Depends on your usage, experience and passion.  Personally, I love the Rotax 912iS - it is robust and provides incredible in flight and post flight feedback (especially when coupled with the Stock EMU912iS EVO unit).  We plan in building ours with this combo, having hundreds of hours on our 701 with the 912iS.  Having said that, you pays ya money and makes ya choice - and the options are many (As Paul has said).

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Permalink Reply by John Austin on September 25, 2014 at 7:22am

Ditto the previous remarks!  I've always advised people to first, define their "mission" for flying and then choose the appropriate plane. The same goes for engines! What's your "mission" or priority? Some enjoy building so much, they build their engine, so the Corvair comes to mind - it probably is or can be the least expensive option. The Viking is developing a following and relatively less expensive than most of the other options save the Corvair. Of course, Corvair and Viking are auto conversions and the history of auto conversions is somewhat checkered, but the Corvair has stood the test of time and is very reliable. The Viking is relatively new and has a short track record so far. The O-200 is very popular - one of the original engines used in the 750 - and can be relatively inexpensive if you buy used and refurbish and relatively expensive if you buy new! It's attractive also because nearly any aircraft mechanic in the world is familiar with it's maintenance and repair. The Jabiru 3300 is a simple, direct-drive purpose built aluminum aircraft engine and is probably "middle of the pack" in expense. It is also relatively light and powerful. However, since it is a 6 cylinder, air cooled engine in a low speed, high drag airframe, it requires some thoughtful tweaking to achieve good cooling. (I know, I've got one!) The Rotax seems the most popular and with water cooling it's probably the easiest to "plug and play" and go flying! However, my hangar-mate has a Rotax and seems to have to do a lot more maintenance than I do with the Jab. It's also more expensive. One personal observation is that it has a distinct sound very different from the rumble of "normal" airplane engines and does curious clunks and shudders as it shuts down. None of this is technically important ... it's just different! UL also seems to be coming-on as a new player and their engines look very impressive, but they are also relatively expensive, too.

I think that Zenith has a great marketing plan in that you have so many choices for engines!

John

N750A

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Permalink Reply by João Carlos on September 25, 2014 at 10:50am

Thanks for everybody. Despite  my experience as a helicopter airline transport pilot (onshore / offshore) + 12,000 total flight time and fixed wing (commercial license multi/IFR) i wil learn a lot with you, hoping to become suitable for the CH 750. Sorry for my english

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Permalink Reply by Wayne Tyson Jr on September 28, 2014 at 12:44am

First, don't apologize for your English. It's better than some native speakers. In any case, all that is necessary is to be understood. I might apologize/apologise for my deficiency in lacking Portuguese. We American's, as professor Higgins might say, ". . . haven't spoken it for years."

As to engines, you should have a look at Walt Snyder's post that summarizes most or all of those that have been used on 750s, including their weights. Mine has a Continental IO-240(B)--four-cylinder, fuel-injected, 125 hp. It may be too heavy. With 8 pounds of lead in the tail and "steam" gauges, the aircraft posts an empty weight of 895 pounds. That's heavy, and flying it at a maximum gross weight of 1320 pounds (the US light-sport law), something has to be left behind. You can probably add another 100 pounds or so to your useful load, so this will perhaps be no problem for you. I bought this aircraft essentially finished, from the builder's widow. Her husband was a master builder who had built at least two prize-winning aircraft, and his workmanship was par excellence!

I'm not sure that I would have chosen the heavier engine. It is more powerful, and I originally reasoned (in ignorance) that the extra power would more than make up for the extra weight, but I have not yet determined the answer to that issue. It's performance is impressive (to me, at least, a rusty pilot who hadn't flown since the 1990's until I got a fresh Biennial Flight Review last year), but as Austin says, it depends upon one's mission. I wanted performance, I wanted to fly sooner than later, and when I saw this airplane I knew that I wouldn't have another chance to buy one this well-made, so I took the plunge.

My good friend who is a long-experienced builder and A&P mechanic urged me to go with Continental, but after riding in John Austin's 750 with the Jabiru 3300, I must say that I was favorably impressed. Of course, there are many people who curse the "Jab," but if you pay close attention to John's comments, I suspect you might be ok with it. Someday, I would like to see a "fly-off" of 750s with all the different engines, with the engine being the only variable (all configured and weighing the same). John has been an invaluable asset to me, as he is to this forum. I've seldom met such an unbiased person.

As to mission, I wanted all the performance I could get for my money. I don't yet know whether the IO-240 is the answer, but it seems to be the only one on a 750 so far. You might want to price them, and see how good the service and parts availability is in Brazil. Or Portugal?

WT

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Permalink Reply by João Carlos on October 18, 2014 at 7:54am

Dear Sir

I`m from Brazil. I`m selling a small house then i`ll have money to buy my CH 750.

Tipically the more powerful engine, the havier it is. 

Jabiru 3300 (120hp) but ramp weight +- 84 Kg  -  Rotax 912S (100Hp) ramp weight +- 64 Kg

 You said  "something has to be left behind"  and i`m thinking about it.

Thanks for your explanation.

João Carlos

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Permalink Reply by Wayne Tyson Jr on October 28, 2014 at 12:35am

Yes, the IO240 is heavy, and I'm not sure whether the extra hp is worth the weight penalty or not. On the other hand, I'm also not sure if the 912S is superior performance-wise. Day before yesterday, a friend had to dead-stick his plane with a 912S onto a country road. He hasn't yet diagnosed the problem, but a leaky carb may be the reason. He's lucky he didn't burn. Burning seems to be the worst possible problem. Fuel off and a fire extinguisher operable from the cabin? Parachute? (On the pilot and passenger, not the airplane.)

I'm also wondering about torque and takeoff; will post when I find out.

I would like to see comparative takeoff data at gross at various density altitudes. I plan to check this out for my plane soon. Landing data for these conditions too.

Any others with info on this that will help Carlos and me understand this better?

WT

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Permalink Reply by Geoff Klestadt on October 28, 2014 at 3:28pm

My "mission" involves a return trip of 184nm each way - there and back from a desert resort - Arkaroola to "The DIg Tree" a major Australian historical site in the desert where Two explorers perished around 1850. So my main determinant is range - I chose the Rotax 912 iS for its fuel economy. Hopefully flying in Six months from now. Skytek has done a great job with the FWF kit...but its an expensive engine/FWF combination compared to a O-200

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Permalink Reply by Wayne Tyson Jr on October 28, 2014 at 4:29pm

Google gives me a location for Burke and Wells Dig Tree at -27.702004, 141.006122

It wouldn't be the first time it has steered me wrong. I don't see airstrips at either location, but some dirt areas from which one might operate a 750.

I'd be interested in data on every engine and 750 combination's performance at gross weight . . .

W

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Permalink Reply by Geoff Klestadt on October 28, 2014 at 4:54pm

Dig tree reference on Google Earth is wrong. Try 27.627064 S, 141 081574 E.

There is a 3000ft dirt runway that also doubles as the road. The landing fee and entrance charge is $11.00 car or aircraft.

Its about 180 - 190 nm to Arkaroola Village airstrip as the crow flies. I try to go up there every winter. Summer? Not so much.

http://www.arkaroola.com.au/

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Permalink Reply by Wayne Tyson Jr on October 28, 2014 at 10:47pm

Thanks; I see some roads, but no habitations. Thanks also for the entree into a bit of Australia history and ethnobotany.

W

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Permalink Reply by Geoff Klestadt on October 29, 2014 at 4:05pm

You are right, roads, but no habitations. Australia is a big place, bigger than the lower 48 states but with only 23 million people who live primarily on the coast because the interior is desert.

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