MV-22: Demo Ride As Tiltrotor Heads For Prime Time
New River, NC., July 13:- USMC pilots demo’d an MV-22 Osprey here for this correspondent taking their aircraft to the currently cleared maneuverability limits in a routine which seemed to re-write the rules of rotorcraft operational capability.
The 34-minute flight, into a practice area near the MCAS New River base for the Osprey test and evaluation squadron showed conclusively the Osprey is rugged, smooth and capable of almost jaw-dropping acceleration to cruise speed from a hover.
The flight – for officials, contractors and media – marked the successful completion of OT IIG, the intense series of tactical and operational trials carried out here to qualify the Osprey for full rate production, most likely beginning this September.
Pilots Lt Col Chris Seymour and Maj Logan Depue lifted Osprey tail number 6484 off the New River runway at 1426 today, immediately accelerating by bringing their proprotors to the full forward position in the early stages of the climb.
Our station in the back of the half-full cabin (fully loaded an Osprey can carry 24 troops) pre-empted seeing the data displayed on the MFD, but a pre-briefing suggested the aim was to reach 250 KTAS as quickly as possible after taking off from the seal-level, 92 deg F runway.
Ground run was minimal – 50 yards at most – but what followed was a thrilling sense of speed building up. Acceleration was linear and strong. A ‘clue’ that cruise flight mode was being set up was the lowering of proprotor RPM to about 85 percent of the take off revolutions.
This is an automatic aspect of tiltrotor flight – one of many new parameters that pilots (and observers) long used to the characteristics of large transport rotorcraft flight will have to get used to.
The aircraft was then put through a card of maneuvers that included an assault approach, numerous hovering exercises and a high speed ‘break’ over the field at 2,000 ft prior to (a similarly thrilling) approach to an approach speed of around 100 KTAS.
The Marines had pulled out the stops on this flight which was accompanied by a sister ship that performed various maneuvers to take up a variety of formatting positions on our aircraft. A lowered rear ramp – as well as an open side door at the crew chief position on the front right side of the aircraft - allowed photographers a unique series of shots of Osprey’s appearance in flight, up to now a commodity that could only be obtained through a controlled process involving program officials.
The new attitude of openness on behalf of these same officials marked a definite first for the Osprey program and was intended to mark – and celebrate – what Lt Gen Mike Hough, USMC Deputy Commandant for Aviation called a ‘great day’ for both aviation and the Corps.
In flight (in the cabin) the Osprey appears somewhat quieter than larger helicopters, but its most noticeable characteristic was its nimbleness.
Turns both left and right were reached at a rate of what appeared to be about 60 degree bank angles in less than five seconds - the higher forward speed contributing to a definite sense of ‘g’s felt.
The aircraft has been criticized for a lack of low-level maneuverability, but Seymour and Depue were having none of it: they racked their aircraft around at heights of between 100 and 200 ft AGL.
The aircraft was highly stable in air made gusty by on and off distant thunder storms. Ospreys are currently cleared to bank angles of up to 60 degrees and pitch attitudes of between 20 and 30 degrees, but these envelope limits will be expanded as a two-year program run by Navair at Pax River gets underway.
‘We want to make it more maneuverable – the word is for it to be more ‘evasive,’’ said Col Glenn Walters, CO of VMX-22.
A squadron pilot said the demo ride was ‘close to, but not actually at,’ the maneuverability limits the aircraft is currently capable of .
Following the overhead break into a short landing pattern, the crew slowed the aircraft by pulling torque back to about 30 percent, an act which immediately brought the speed down very noticeably. In the back, the feeling was that the aircraft had perhaps run into mud, so smooth and predictable were the deceleration forces. This writer – mindful of the challenge to yaw control such things present in a conventional helicopter – noticed the aircraft was very precise in this axis.
What more to say about impressions of Osprey flight at this point? Overall it’s clear certain thresholds set by generations of rotorcraft up to now have been decisively breached.
The Osprey flies faster, climbs faster, is smoother – and quieter.
Proponents have long said this was case but up to now have been unable to prove it to anyone outside the pilot/engineering fraternity.
Critics have stood their ground claiming maneuverability issues, inherent handling flaws and overall maintainability will make the Osprey case unsupportable.
OT IIG results – refute all these things and more. But if that’s not enough just one simple maneuver, pick-up off a landing site – like any old helicopter - followed by an immediate boost from zero to 250 knots in just a few seconds – should be enough to convince them a generational change in the way rotary wing aviation does business is at hand.
- David S. Harvey