The first combat tiltrotor squadron played a key role in the Marine Air Ground Task Force integration training on 1 March 2007; the squadron was subsequently deemed to have completed a successful transition from CH-46s Sea Knights to the MV-22B Osprey.
As baptism by fire looms, how combat-ready are the Ospreys of the first operational squadron (VMM-263)? Can they be supported in the field?
Given the Osprey’s glitch-plagued quarter century of development, those are loaded questions. In weighing the evidence, a number of issues should be considered.
MV-22Bs are restricted from taking radical evasive maneuvers. Planned three-barrel nose turrets for clearing hostile landing zones have been replaced by ramp-mounted guns that fire to the rear and impede troop egress.
Despite the technical review warning of component and flight control computer obsolescence issues conducted by US Naval Air Systems Command (NAVAIR) in 2003, all V-22s were grounded last month because of faulty Texas Instruments chips in their computerized flight control systems.
A further issue that needs to addressing is continuing engine fires. A fire in 1992 caused a crash that killed seven people. Other fires followed as recently as 2005 and 2006.
On 6 December 2006, 54 seconds after an MV-22B landed at US Marine Air Corps Station New River, North Carolina, yet another Osprey fire severely damaged an engine and its nacelle. Had the aircraft been in flight, crew members could have died. In this incident, an “engine air particle separator (EAPS) hydraulic pressure tube… ruptured,” spraying volatile hydraulic fluid into the hot section of the infrared suppressor. February’s detailed final accident report traced the event sequence back to a “severely worn impeller shaft and journal bearing.” The cascading effects caused vibration, rapid flow and pressure spikes of 2,000 to 3,000 psi above the standard 5,000 psi (which resulted in fatigue cracks in the thin-walled 0.25-inch hydraulic line’s brittle titanium alloy), tube fracture and fire.
The February engineering investigation report recommended among other actions redesigning “the EAPS hydraulic system,” as well as the nacelle drainage system, the EAPS blower failure detection system, the infrared suppressor section (adding a fire detector and extinguisher), and software for the leak detection and isolation system. The report failed to mention conclusions regarding the impeller shaft and journal bearing: did poor design, poor subcontractor quality control or inadequate maintenance play a role? It begs the question whether these redesigned and rebuilt systems will be installed in all aircraft before combat deployment.
As hydraulic woes continue, so do software glitches. A small sample includes the following problems:
* According to a February 2007 NAVAIR maintenance memo posted on Military.com, an MV-22B’s EAPS blower failed when a mission computer performed an uncommanded reset on the ground, causing the motor to run with no case drain flow. “Loss of aircraft and aircrew” was listed as possible in-flight outcome. * An early 2006 maintenance assessment found that faulty software had caused “uncommanded wing rotation during the blade fold wing stow sequence,” with potential fuselage damage and delay of flight deck operations. * On 27 March 2006, a digital engine control software problem triggered uncommanded takeoff of an Osprey whose engines had been idling, then reduced power; slamming back to the ground, the aircraft snapped off its right wing. It apparently will not return to flight status.
An internal April 2006 memo reported that the Second Marine Air Wing’s maintenance and supply Tiger Team had assessed the Osprey’s operational supportability. Their findings are disturbing.
For example, training squadron VMMT-204 (flying MV-22As) achieved roughly a 60 percent mission capability rate with 50 per cent full mission capability versus requirements of 82 per cent and 75 per cent, respectively. The number of repair requests was 3.7 times the expected amount. Poor reliability in the technicians’ portable diagnostic devices hindered their ability to troubleshoot glitches. Warm hangar temperatures also caused maintenance ground stations to overheat, resulting in shutdowns or failures.
Premature component failures increased demand for technicians but maintainers faced hiring restrictions and reduced logistics funding. Undeniably, when combat squadrons “operate in harsh environments from remote land bases and naval ships … supportability will be more challenging”.
In the year since, how have the improved Block B aircraft fared?
According to InsideDefense.com, the US Air Force’s mid-2006 “operational utility evaluation” of four CV-22Bs at Kirkland Air Force Base, New Mexico, found mission effectiveness and maintenance efforts “degraded by poor aircraft availability” caused by “frequent part and system failures, limited supply support, and high false alarm rates”. As for the Marine Corps, in a February 2007 memo, V-22 testing officials at Patuxent River, Maryland, reported MV-22B readiness for Operational Test and Evaluation to be jeopardized by:
* excessive false alarms and aborts, reducing availability and increasing maintenance loads; * environmental control systems that still expose troops to extreme cold or heat stress; * “multiple cargo handling system deficiencies” that, despite system redesign, still hinder operations, requiring hand loading of cargo and mission delays; * delays and dangers to aircraft and personnel during austere operations, caused by filters and “components clogged and damaged by sand, dust, dirt, and grass,” including in the environmental control system, the crucial avionics bay cooling system and heat exchangers for gearboxes controlling the tilt axis, the backup midwing drive system and the proprotors.
This is only a partial listing of the problems.
With lives at stake, the question bears repeating: how combat-ready and maintainable is the MV-22B Osprey?
LEE GAILLARD is a writer on defence and aviation issues. He is a contributor to the Center for Defense Information’s Straus Military Reform Project.