Small Coaxial Helicopter SCH-2A

NJpilot

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Do the counter rotating blades in coaxial helicopters reduce the danger of applying uneven bump forces that can flip conventional choppers?

Next time find a narrower place to fly this thing with even more power lines. :oops:
 

birdy

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I’d have one ina hart beet if it hada propa engine init👍
 

Kevin_Richey

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That website shown in Post #1 shows a US east coast distributor located in Merritt Island, FL, CFX Aero LLC. An Andrey Vegger is the contact person.

China is represented as another distributor as well as the owner, Miro, who handles the European market & other countries. Miro says he is in negotiations w/ a west coast US distributor.
 
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Illini85

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I would like to hear from someone experienced discuss whether a coaxial design can adequately autorotate. I would think that friction in the gearing might be an issue as well as the shorter rotor blades.
 

anvegger

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Good morning Folks For those of you in the USA who would be interested in our program My name is Andrey Vegger My phone number 603 409 9093 and location is KCOI in Sunny Florida (Space Coast Cape Canaveral Merritt Island) Feel free to reach out for any questions comments and concerns.
 

flyboyof3

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Small Coaxial Helicopter SCH-2A is one of the lightest manned coaxial helicopter in the world and is compliant to US FAR Part 103 Ultralight Vehicle rules.​


Pleas

Small Coaxial Helicopter SCH-2A is one of the lightest manned coaxial helicopter in the world and is compliant to US FAR Part 103 Ultralight Vehicle rules.​


Can some one please explain to me how a Coaxial helicopter turns and flies. I know how regular helicopters fly and turn.
 

anvegger

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This video explains the principals of coax rotor technology. Please refer to CC settings to get the auto translation into language of your choice
 

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Ted Meyer

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Hi, new here but not to flying a gyro. This helicopter was at Oshkosh this year. Wondering if anyone saw it. I was told it was only allowed to hover because of too few of hours on it. I was also told by a salesman for this company that he has sold four machines. I am hoping for some autororation videos. Imagine that. Thanks
 

Kevin_Richey

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I have been asking for the same (A.R. videos). There are two short A.R.s, one in the June 29 comments as well as another short A.R. in the video in a post on August 6th. RotoTrek LLC is Mirocopter's west coast US distributor, in Murrieta, CA. See them @:
 

Ted Meyer

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Thanks Kevin, I have seen several videos of it hovering and flying in the grey area. Seen one auto, you can hear power cut anyway. I see he did not want to go full down. Hopefully that video is coming. I have talked to the dealer from Califonia at Rototrek. He said he has one coming and will get lessons in some kinda helicopter. I am very curious about the transition from a conventional helicopter to this type. I suppose there is a safe airspeed in an engine out scenario for those tail fins to be responsive with yaw.
 

Kevin_Richey

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I noticed in those limited, short duration autos they filmed, that the yaw didn't seem affected @ all.
I had been wondering if those tail fins have much authority in an auto...
I'm assuming the downwash is greatly reduced when in autorotation.
 

Oskar

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Many people told me that I would loose directional control in my electric tail helicopter in an auto because the tail isn’t driven by the main rotor. In real life directional control during an auto is superb, I’ll try to explain why this is so.

What many people tend to forget is that in an auto the glide ratio is roughly 1:4.This means that horizontal speed is roughly 4 times as large as vertical speed. Adding to that is the fact that aerodynamic forces are typically equal to the square of airspeed, double the airspeed and aerodynamic forces don’t double but go up by a factor of 4. During an auto the aerodynamic forces due to forward speed are thus roughly 16 times as large as aerodynamic forces due to vertical speed downwards. What keeps the SCH-2A (and my electric tail helicopter straight) is an effective vertical stabiliser, and you don’t need to look very hard to find it.

A gyrocopter works the same way, once you have enough airspeed the vertical stabiliser is what keeps the nose pointing in the right direction. Taking your feet off the pedals won’t cause you to loose directional control.

When forward airspeed drops to zero everything changes of course, because the vertical stabiliser now becomes ineffective. In a gyro the horizontal stabiliser and prop wash (if the engine is still running) now play a dominant role. If the engine is not running the horizontal stabiliser causes the nose to pitch down, airspeed builds up and the vertical stabiliser starts working again.

An auto at zero airspeed in a SCH-2A will result in yaw control reversal, to get out of that it’s necessary to build up airspeed again. For a low hour pilot that might prove challenging.

The safest way to fly a SCH-2A at auto heights is to always fly at airspeeds where the vertical stabiliser is dominant, that way yaw control reversal will never be an issue.
 

btd1982

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The dam yaw pedals work backwards in every flying machine if you ask me. 😉
Reversal in an auto would help in my case.

It says in the sch2a info that coaxial's have a 20% slower decent rate in an auto which is interesting. The whole machine looks very well made and there's certainly no excess weight. Hope it does well.
 
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