Electric tail rotor; an alternative?
Join Date: Dec 2011
Location: UK
Posts: 44
Some interesting reading.
Overview of NASA Electrified Aircraft Propulsion Research for Large Subsonic Transports.
https://ntrs.nasa.gov/archive/nasa/c...0180000361.pdf
GRC3: Integration of Innovative Electrical Systems for Rotorcraft (pages 12 & 13)
http://cleansky.eu/sites/default/fil...eport_2015.pdf
But are helicopters the future?
http://evtol.news
Upcoming lecture by Nick Lappos.
https://vtol.org/news/lappos-selecte...olsky-lecturer
.
Overview of NASA Electrified Aircraft Propulsion Research for Large Subsonic Transports.
https://ntrs.nasa.gov/archive/nasa/c...0180000361.pdf
GRC3: Integration of Innovative Electrical Systems for Rotorcraft (pages 12 & 13)
http://cleansky.eu/sites/default/fil...eport_2015.pdf
But are helicopters the future?
http://evtol.news
Upcoming lecture by Nick Lappos.
https://vtol.org/news/lappos-selecte...olsky-lecturer
.
Last edited by gevans35; 2nd Dec 2018 at 07:45.
Join Date: Jan 2011
Location: on the cusp
Age: 48
Posts: 217
Originally Posted by tigerfish
Sadly TC, as so often is the case, this forum has been invaded by many armchair flyers who have no idea about actual operational Air operations . Best leave to their playtime air ops games!
TF
TF
Join Date: May 2016
Location: Norway
Posts: 33
Just to make it clear, my comment about autorotation was with the assumption that the generator would then be dead, and putting enough heavy and possibly explosive batteries in a helicopter to have that as a backup doesn't seem remotely realistic to me. I didn't think of that the gearbox could drive the generator, which I realize now would be the only sensible thing to do.
The autorotation comment was just meant as an example of new problems that would arise with such a "hybrid" system. I still think the main points are that I can't imagine that such a system as a total would be as reliable as a driveshaft and a gearbox, and that it would be much less efficient. I could be wrong, but I still have a hard time seriously thinking of electrifying the TR to reduce the risk of failure.
The autorotation comment was just meant as an example of new problems that would arise with such a "hybrid" system. I still think the main points are that I can't imagine that such a system as a total would be as reliable as a driveshaft and a gearbox, and that it would be much less efficient. I could be wrong, but I still have a hard time seriously thinking of electrifying the TR to reduce the risk of failure.
Join Date: Nov 2006
Location: After all, what’s more important than proving to someone on the internet that they’re wrong? - Manson
Posts: 1,525
You do know you can autorotate with or without a working tail rotor right?
Join Date: Apr 1998
Location: Mesopotamos
Posts: 1,307
Suppose you have to hover next to a cliff or hangar with some serious crosswind. Consider the following:
Is a fixed pitch variable speed electric motor dynamic enough to hold the tail steady? What about tail rotor rpm wind down when the gusts abate, do you need tail rotor brakes?
Perhaps variable pitch constant speed is the better electric option of the two. Now how do you manage power available on two different systems. Will the electric motor run out of puff while the coal burners are just warming up? Are bigger electric motors needed along with all the penalties that introduces?
Some of us like to roll the helicopter in tiny amounts just using the pedals, will the electric fan at the back take this away from us?
Now if you are gunna stick an electric fan at the back at least allow it to pivot around 90 degrees to provide forward thrust.
Is a fixed pitch variable speed electric motor dynamic enough to hold the tail steady? What about tail rotor rpm wind down when the gusts abate, do you need tail rotor brakes?
Perhaps variable pitch constant speed is the better electric option of the two. Now how do you manage power available on two different systems. Will the electric motor run out of puff while the coal burners are just warming up? Are bigger electric motors needed along with all the penalties that introduces?
Some of us like to roll the helicopter in tiny amounts just using the pedals, will the electric fan at the back take this away from us?
Now if you are gunna stick an electric fan at the back at least allow it to pivot around 90 degrees to provide forward thrust.
Join Date: Sep 2017
Location: Canada
Posts: 312
Originally Posted by dClbydalpha
How much did you pay for it? What kind of certification did you get with it?
I overpayed obviously. I thought Walmart had the best price, but then I found it at Best Buy for less. #rippedoff
there was a sticker inside the airframe. Mostly in Chinese that had Insp.45 on it. I assume this was the manufacturer QA inspector. I bet he knows his stuff.
the things I learned on this thing would shame Chuck Aaron and his 105. He's got nothing on me.
Join Date: Mar 2004
Location: hayling island
Posts: 249
I like this idea, main problem I can see is the tail rotor will have to keep spinning in flight otherwise there could be damage to the tail rotor blades or mechanism during start up and slow down.
Perhaps a ducted one would be superior????
Perhaps a ducted one would be superior????
Thread Starter
Join Date: Nov 2008
Location: UK
Age: 62
Posts: 913
Originally Posted by timprice
I like this idea, main problem I can see is the tail rotor will have to keep spinning in flight otherwise there could be damage to the tail rotor blades or mechanism during start up and slow down.
Perhaps a ducted one would be superior????
Perhaps a ducted one would be superior????
Last edited by chopjock; 2nd Dec 2018 at 12:13.
Join Date: Aug 2000
Posts: 1,655
if these things that might appear ludicrous aren't looked at then nothing goes forward. I remember my basic rotary wing instructor at Wallop told me ( he started as a Sycamore pilot ) that they thought it was impossible to put a gas turbine in a helicopter when he started in the 1950's. That idea was obviously a non starter as well
Moderator
Join Date: Aug 2006
Location: Ontario, Canada
Age: 59
Posts: 4,444
The assumption that a motor would be as heavy as a TGB, IGB, MGB tail pickoff and driveshaft is not one that I would make.
I am a helicopter pilot, and have undertaken design studies for an electric powered Cessna 172 STC (program may continue) and an electric powered R22 (program will not continue). Electric power in aviation has a bright future, in a rather narrow band of application, which I opine does not include helicopters in the foreseeable future.
Join Date: Dec 2011
Location: UK
Posts: 44
Originally Posted by Pilot DAR
Electric power in aviation has a bright future, in a rather narrow band of application, which I opine does not include helicopters in the foreseeable future.
Edit: Here's an example...
https://newatlas.com/rolls-royce-evtol-air-taxi/55466/
.
Last edited by gevans35; 2nd Dec 2018 at 13:40.
Join Date: Jan 2011
Location: on the cusp
Age: 48
Posts: 217
Originally Posted by Pilot DAR
... which I opine does not include helicopters in the foreseeable future.
Motors, generators and actuators are already used, so we know how to design for certification, nothing daunting there.
As has been pointed out previously the technology is already here. It's simply about the investment.
Join Date: Nov 1999
Location: UK
Posts: 1,295
- I'm sure there's a lot of computer control in most modern helicopters already, but this would have to be entirely computer controlled to be at all flyable. That would open up a new can of worms when it comes to safety. I know that "fly-by-wire" is popular these days, but personally I only consider it "safe" as long as everybody is equipped with ejection seats.
As to fly-by-wire; so I take it that you don’t fly on any Airbus and only on some Boeings and turbo-props?
Airbus 320 family and 330 each have 5 FBW computers, and can remain flying aloft without any of them.
PS: can helicopters have ejection seats ??
Join Date: Sep 2017
Location: Canada
Posts: 312
Originally Posted by Washeduprotorgypsy
PIlot DAR,
I am curious to know the weight and horsepower of an electric motor suited to a Cessna 172 retrofit.
CAn you give us a ballpark range?
I am curious to know the weight and horsepower of an electric motor suited to a Cessna 172 retrofit.
CAn you give us a ballpark range?
https://www.flyingmag.com/news/two-place-electric-cessna-172-skyhawk
