Reports dating from June 1999 indicated chafed hydraulic lines while an inspection of eight MV-22s also discovered chafing. The USMC recommends that NAVAIR and Bell Boeing review hydraulic line clearances and wiring bundle placement "and investigate the possible redesign of the hydraulic system to prevent dual system failures". Berndt noted that Bell Boeing issued a service bulletin a year ago "identifying the problems with chafing and hydraulics". He says "maintenance crews performed all inspections as per regulation". Bell and Boeing say they will not respond to the report's conclusions until they have reviewed it and made recommendations. Source: Flight International