No matter how well an engine is designed it has the potential to
malfunction at some point during its lifetime. The possibility also
exists that something outside the pilot's control, like bird ingestion,
could cause an engine or lift fan to fail. If the proposed VTOL
aircraft is to be a practical size, it must use a propulsion system
with fairly high fan or disc loading, which is also necessary for good
cruise efficiency. A more highly loaded fan (>30 LB/ft.) is not
capable of auto-rotation. Therefore, any aircraft using higher disc
loading will need a back-up system or systems to ensure passenger
survival in case of a critical component failure. Great care was taken
developing a production model volantor which would provide safety and
comfort as well.
The most important issue in aviation is safety.
So, the following safety features were designed into our volantor to
help provide a safe alternative to ground transportation:
-- In the unlikely event of an engine failure
sufficient power remains to ensure a safe and comfortable landing.
Since the M400 has eight engines, one or more can fail and the Skycar
will still operate safely. Unlike any light helicopter or airplane, the
M400 Skycar has four engine nacelles; each with two Rotapower engines.
These computer-controlled engines operate independently and allow for a
vertical controlled landing should one engine fail. Top
| • Redundant Computer Stabilization Systems |
-- The Skycar has redundant, independent computer
systems for flight management, stability and control. Should a computer
problem occur backup systems would take over seamlessly. M400 has
multiple independent computers for flight management and the design
prevents a single-point failure from adversely effecting the
performance of the aircraft. Top
| • Redundant Fuel Monitoring |
-- Multiple systems check fuel for quality and quantity and provide appropriate warnings. Top
-- In the unlikely event that insufficient power
is available to hover, the Skycar's aerodynamic stability and good
glide slope allows the pilot to maneuver to a safe area before using
the airframe parachutes. Top
| • Automated Stabilization |
-- Since computers control the Skycar flight
during hover and transition, the only pilot input is speed and
direction. Undesirable movement of the Skycar due to wind gusts is
automatically prevented. Top
| • Inherent Simplicity of the Engines |
-- Rotary
engines have very few moving parts and therefore require very little
maintenance and have little opportunity for breakdown and wear. Top
-- Each nacelle fully encloses the engines and
fans, greatly reducing the possibility of injury to individuals near
the aircraft. The volantor's VTOL lift is obtained via airflow through
the four ducted fan propulsion nacelles which is redirected downward by
deflection vanes during vertical takeoff. Top
--
Even in the instance of complete power loss you and your passengers are
protected. The two airframe parachutes, front and rear, will guide the
volantor safely and comfortably to the ground without incidence and can
be deployed in the event of a critical failure of the aircraft. With
the parachutes, the pilot, passengers and the Skycar can be recovered
safely. Parachutes developed for the ultra-light aircraft industry,
that are ballistically ejected, have demonstrated reliable vehicle
recovery above 150 feet. Recovery is possible at a much lower altitude
if the aircraft has a modest forward velocity or if a spreader gun is
used to spread the parachute canopy. The best primary system should use
the minimum number of engines necessary together with sufficient power
to hover after the failure of one engine. A multi-engine system also
interfaces well with a back-up parachute system since the time between
consecutive engine failures should allow sufficient opportunity for the
parachute to be deployed. A single engine failure in a VTOL aircraft
with eight independent ducts and one engine per duct would require 54%
reserve power in order to continue to hover. The same number of engines
arranged in four nacelles with two engines per nacelle requires 36%
reserve power to accommodate an engine failure. The safe operation of a
VTOL aircraft requires that during hover it operate as close to the
ground as possible (<25 ft.) and that transition to forward flight
occur as quickly as possible. With the loss of an engine at 25-ft
altitude the vehicle could be landed very quickly without incident.
Above 25 ft altitude one can assume that the vehicle is moving forward
and generating some aerodynamic lift so that a second engine failure
should not be as critical. In the case where a critical number of
engines fail and transition is not complete, aerodynamic lift can
extend the flight time in the critical period before the parachute is
fully deployed. Thus, deployment could occur at relatively low
altitudes (<25 ft.) particularly if a spreader gun is used. In any
case, a new concept aircraft can be expected to undergo the unexpected.
Thus, overlapping systems to ensure passenger safety would be
appropriate and should be mandatory. Top
-- The Skycar can land almost anywhere, and
therefore avoid dangerous situations created by a sudden weather change
or equipment failure.
By emphasizing simplicity, durability and
redundancy, Moller is making safety an inherent attribute of this
revolutionary aircraft. Top
