Two Place Mosquito

bryancobb

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Has 70' been indicated in some way by Innovatortech or is it just a question? If they could sell the kit for about that price, it would be a success.
My guess is...It could not be done. The base engine is around $25k. The main gearbox will cost them another $15k to manufacture unless they use straight cur spur gears and more or less copy a Brantly planetary box.

Rotorway shows that even a $100k 2-seat kit barely makes enough money to keep the company alive.

Also, The Mosquito organization chooses to stay small, keep demand up, and prices high to give the guys at the factory job security. That has been working so I doubt they would change their profile. Selling single seaters as cheaply as possible was never their goal.

My prediction is ... finally a FLYABLE, RELIABLE, WELL DESIGNED two-seat kit helicopter, but the price will be $110-$120k.
 

StanFoster

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I agree with Bryan. It will be an excellent 2 place helicopter, and over $100k.
 

Sandstream

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My guess is...It could not be done. The base engine is around $25k. The main gearbox will cost them another $15k to manufacture unless they use straight cur spur gears and more or less copy a Brantly planetary box.

Rotorway shows that even a $100k 2-seat kit barely makes enough money to keep the company alive.

Also, The Mosquito organization chooses to stay small, keep demand up, and prices high to give the guys at the factory job security. That has been working so I doubt they would change their profile. Selling single seaters as cheaply as possible was never their goal.

My prediction is ... finally a FLYABLE, RELIABLE, WELL DESIGNED two-seat kit helicopter, but the price will be $110-$120k.
I like your prediction, $120 would be a very reasonable price for a well designed two seater.

May I ask you what your thoughts are about straight cut spur gears? Would that be a "short cut" solution? What would the preferred gears be?
 

bryancobb

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...May I ask you what your thoughts are about straight cut spur gears? Would that be a "short cut" solution? What would the preferred gears be?
Sand,

A spur gear with straight teeth is the cheapest and quickest kind of gear to make. You can make them without any fancy machinery.

A single-stage planetary gearbox, like a Brantly has, is a piece of cake to assemble and there is almost nothing adjustable. The parts in the assembly set all the gear lashes, etc. and it is not very critical.

When the weight of the helicopter is carried by the gearbox, there's no change in geometry of meshing teeth. The load is parallel to the teeth.

Spiral-bevel gears are "Cad-Ill-Ack" and used in most small helicopters. They are finnicky to set-up. The tooth mesh geometry varies as you maneuver because the gearbox case flexes and the load is trying to pull the meshing gears apart. Their teeth "ROLL INTO MESH" instead of sliding and they are quiet and smooth.

THE BIG BIG ISSUES WITH SPUR GEARS AND PLANETARY GEARBOXES ARE THEIR NOISE LEVEL AND HOW TO GET POWER IN SINCE THE SHAFTS AND ALL ROTATING PARTS HAVE THEIR AXES SITUATED VERTICALLY AND MOST ENGINE INSTALLATIONS HAVE THE CRANK SITUATED HORIZONTALLY!!!
 

baronpilot

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The Swift looks great, but if this is the current progress it will be another 2-3 years before one is available for sale. I'm betting on $130-$150k flying.
 

Sandstream

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Bryan,

Thanks, that was all new educating information to me. It will be interesting to learn more about Uptigroves choice of gears in the master gear box for the Swift.
 

Sandstream

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The Swift looks great, but if this is the current progress it will be another 2-3 years before one is available for sale. I'm betting on $130-$150k flying.
Don't know how much development is still needed? Looks like the engine and master gearbox is where it should be. Rotorhead, rotorblades, mast/driveshaft done.

Flight controls, avionics, tailrotor with gearbox and driveshaft remaining to be done. And "the little things".

Really hope they can begin flight testing soon. Composite FX's website states both this summer (2014) and the end of 2014. Maybe something in between then? :)
 

Sandstream

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I like the fenestron tail rotor design for the protection. And it looks nice :).


Picture from Oshkosh 2014 photoalbum at Innovatortechs homepage.

Sent from my iPad using Tapatalk HD
 

bryancobb

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The fenestron alone, will take a year to get right. The MRGB may not have any "guts" in it. Who knows? It's a sharp helicopter by it's way beyond my budget.

Sitting in the seat with legs straightened out and horizontal will be tough on the knees after 1/2 hour.
 

Sandstream

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Question is if it's going to be a real fenestron with a lot of blades? Might be a conventional tail rotor in the duct. That might, correct me if I'm wrong, be easier to get right (maybe not a year long project?).
Though not a real ducted fan fenestron, it would still look great and offer protection for the rotor and safety for people around the helicopter.
 
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Sandstream

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The fenestron alone, will take a year to get right.
You were on to something there. Good analysis of the difficulties :).
Guess it isn't so easy to make this type of enclosed t/r. But they seem to know what they are doing and were they are going.

From the latest update on Composite FX:

"Fenestrom ducted fan will have to be rebuilt. The shape on the exit side will be sharpened for better airflow. All the metal components shown are have been re-designed in carbon fiber for weight savings".
 

Sandstream

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bryancobb

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The details are not really understood but I sort-of don't like the short driveshaft BETWEEN the upper sheave and the gearbox input pinion.

It appears to have a flex coupling at the rear and an automotive universal joint at the front. I don't know of any certificated helicopters that have a power input shaft that is so long and that heavily loaded.

John U. is a Licensed Professional Engineer (if he is the designer) and I'm sure he has done his homework on this shaft. Just because it's a "different" way doesn't mean it's a bad way.

The head is a masterpiece just like the Mosquitoes'. The bearing arrangement, undersling geometry, and control system will only prove themselves after hours of flying.

Lots of progress can be seen.
 
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Arnie Madsen

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Bryan ... my guess , going by the pictures .... looks like they have the transmission and mast mounted on flexible rubber to absorb the 2-per-rev , same as Bell 47 "cradle" , thus the driveshaft to allow movement. I believe the Bell 206 also uses a drive shaft between the turbine and transmission for the same reason. Hillberg or someone can confirm

Removing most of the 2-per solves a lot of other issues , even though an extra driveshaft is required , this is what I am seeing and "like" on this design.
 
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Soooooooo? Did the Swift show up at Oskosh or what? The silence on this forum is deafening. Especially now that rotor way has come out with the new RW7.
Anybody!!!!!!
 
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