Twisted: Electric Twister aEro and developments

I spent at least 2 hours talking with the H55 team about the electric Twister at Aero Friedrichshafen.

The team cannot be of a better pedigree as they are the same people who designed and built the Solar Impulse 2 - the round the world electric aircraft.

More details and specs on this site:

http://www.hamiltonwatchaero.com/

One of the test pilots I was talking to (Dominique) said he thought the take off distance of the electric Twister was about half as much as a normal Jabiru powered Twister.

It also has a climb rate of 1,700fpm - this does not change with altitude either as the electric motor puts out the same power regardless of atmospheric pressure.

Currently it has a 100kW motor and they are planning on putting a 200kW motor in it next. This will give it a power to weight ratio about double that of an Extra 300.

Also they are building a new wing - which will use the same molds so the profile is unchanged - but there won't be any flaps. In their place will be full span ailerons giving a 400 degree roll rate! The outer wing tips will be 'clipped' too to further improve the roll rate (although this will destroy the Twister's beautiful lines).

Dominique said it is unlike any other aerobatic plane to fly in a sequence as the motor acts as a brake when you are going down (gaining energy as it does so with regen). So the sequence has less change of airspeeds and any downlines can be made longer.

He also said it is virtually vibrationless in flight "Turbine smooth" and with no noise other than the wind rushing past the canopy.

The price of the current electric motor is eye watering though - $100,000.

It only weighs 13kg - if you were happy to have a motor double that weight then the price would come to 1/5th of that - so $20,000.

Exciting times for electric aircraft.

The 200kW version with it's new wing will be a Twister 2.0

Woodcomp variable pitch prop helps performance.

Cut down gear leg fairings with massive gaps.

I think these two split inlets from the NACA duct underneath go to the batteries in the wings to provide air cooling.

Charging plug - takes 1 hour to charge.

NACA duct at the front of the cowl feeds air to the batteries mounted on the firewall - this duct has an integrated rain separator, water and batteries don't mix well.