If the Volocopter is capable of steering itself it must be able to vary
the thrust (RPM for fixed rotors) of each motor so, with a single motor
or rotor failure, the system should be able to maintain controlled
flight by varying the other motors.

Having said the above, stating that all of the referenced helicopter
crashes (with autorotation capability) resulted in fatalities is a bit
disingenuous since you also stated up front that they were fatal
accidents. Not all of the helicopter crashes resulted in fatalities.

And the BRS system is not the cure all. I have one in my Pipistrel
Sinus but it scares the hell out of me. If deployed at too low an
altitude, the result is to be on the end of a pendulum swinging into the
ground. If there are high winds, you'd better be able to get out of the
aircraft lest you be killed in the wreck dragging across the ground.
And then there's the unforgettable image of the flaming Cirrus gently
descending to the ground while the occupants burned to death.

I'm reminded of the Piper Cub - an aircraft so safe that it can only
barely kill you.

On 12/13/2015 2:24 AM, Kilo-Bravo wrote:
O.K., few of my counterargumenters continue to ignore a safety-device called "Ballistic Rescue System". Why? Just because "What I do not know - I do not like?
You insist at the ability of autorotation as best safety device? Sure it´s one thing, but have a look at the list of the National Transportation & Safety Board at the following link:
http://www.ntsb.gov/_layouts/ntsb.av...0-abf8bd4e5421
In this list, you find 1.929 reports starting 1964 until today, only Helicopters and only categorized "FATAL". I have not read all of them, but sure all mentioned Helicopters had the ability of autorotation by design and build. The theoretical ability of autorotation did not safe a single soul in those fatal accidents.
I´m convinced, that many of those victims could have been saved with a build-in BRS, knowing of course, that during a long earlier period of time, BRS did not exist and even this days, there is no adequate BRS on the market for most of those (heavy) choppers.

Or look through that other list, showing the number of fatal accidents with Ultralights, starting in 1982.
http://www.ntsb.gov/_layouts/ntsb.av...3-098dbdc6c804

Sure most of them would have the designed ability to glide to the ground, in case of an engine-failure. But this ability did not prevent any of those fatal crashes.

According to German Regulations, all Ultralights must have a build-in BRS. This device has already saved many lives during the last years. Sure not 100%, but a big number.


Just two examples out of many:
When a Czech made DUO-Banjo came to land at a small German airfield in 2013, the pilot tried to keep hight because he was coming short and was flying over a big forest area. About 500 m before the runway, 100 m above the field, he was to slow and the motorglider with retracted engine went into a sudden spin. He pulled the handle and activated the BRS, crashing into the forest but survived the crash "unharmed". With a common motorglider or glider, he sure would have been killed. Some nice pictures you`ll find at this link:
http://www.frankenpost.de/fotos/nach...467709,2624008

An Ultralight with two occupants crashed into a Ka8-Glider in 200 m hight just about 800 m outside a small airfield in Germany. While at short final, the Ka8 with a student on board turned in to its short final, flying into the Ultralight from the right. The Ultralight was stuck in the fuselage of the glider. As the pilot activated his BRS, both aircraft came down outside the airfield, both aircraft heavily damaged, but all three survived with minor injuries.
http://www.rhein-zeitung.de/region/l...l#.Vm0z3Xv8Mu2

As I look at those pictures, I´m happy about the fact, that I carry a BRS in my glider, which is fitted to the airframe getting me safely to the ground, instead of carrying a parachute tight to my back, not knowing if I get out in time and in adequate hight in order to get the chute inflated befor I hit the ground and wake-up to see I´m dead.

Best regards from Germany

Klaus

--
Dan, 5J