Airframes Out with the old, in with the new The retirement of ageing early-series boeing 747s is freeing up maintenance capacity that can now be used to meet the increasing needs of later variants, which are beginning to reach maturity, albeit with less demanding maintenance requirements than their predecessors. Ian Goold investigates angar space used for around 250 will be accommodated by the capacity 747-400 D checks are expected to [take fewer] boeing 747SP, -100, -200, and vacated by retiring 747 Classics,” says than 25 days.” H -300 Classics is being shared boeing Commercial Airplanes maintenance- by 2015-16, about 111 such D checks a year with younger 747-400s that are subject to economics director Khwaja Ali. “The older will be performed on 747-400s, up a sixth on less intensive maintenance. “More D checks 747s take significantly longer time in D checks the 95 typically carried out annually since 2005, on 747-400s delivered in the past five years due to their ageing, whereas the newer according to Ali. “We need to account for longer 8 MRO Management www.mromanagement.com − March 2011 MROM_Mar11_digital.indd 8 07/03/2011 08:20 Airframes (photo: Lufthansa Technik) [maintenance] duration in the third D checks, events. “boeing has off ered Classic operators and the need for more hangar capacity, but which start occurring in [the coming fi ve years]. an MSG-3 programme that reduces average boeing analysis shows that accelerated Viewed alone, it would indicate a need for 25% D check time by eliminating many tasks and retirement of older 747s – more for fuel burn additional 747 hangar capacity, but the [space] extending many intervals,” says Ali. “The efficiency than higher maintenance costs – being vacated by accelerated retirement of non-routine fi ndings continued to grow due frees more hangar space than is lost to 747 Classics easily absorbs this demand.” to ageing, [but] the net result was still a D check time escalation. The 747-400’s unique calendar-driven reduction in D check [time of] about fi ve days Of the 959 active boeing 747s (as at December inspection schedule means that peaks and – freeing about 5% of hangar capacity.” 2010), some 29.5% – or 283 units – are Series troughs in MRO demand are not influenced The revised maintenance programme has 200s or 300s, which are being retired at a rate of by different aircraft usage among operators. been available since 2002, with boeing saying 37 a year. The fl eet is expected to decline to 818 D check requirements will be largely that it has given participating operators over the next six years, says Ali. governed by delivery dates (and rates), with reduced maintenance labour-hours, as Since entering service with Northwest calendar frequency determined by the well as increased aircraft availability. “The Airlines in January 1989, the 747-400 has seen maintenance programme. programme provides fl exibility to operators a steady increase in scheduled maintenance to package tasks based on their business intervals, with myriad improvements and Reduced requirements requirements and can vary.” modifi cations extending airframe and engine Since boeing instituted a revision of inspection Ali suggests it would be reasonable to life, as well as reducing overhaul costs. Initial requirements for all 747 series aircraft, using suppose that the ageing of the 747 Classics scheduled requirements were: A check at 300 uS Air Transport Association Maintenance fleet implies that hangar downtime for fl ight hours (FH), C check at 15 months (but Steering Group Level 3 (MSG-3) standards D checks increases by 50% for third (and not to exceed 3,000FH), and D check at fi ve about 10 years ago, two signifi cant trends have subsequent) D checks, compared with a years (but not to exceed 25,000FH). emerged: lower D check downtime and 747-400’s first two such inspections. The The model’s maintenance review board reduced frequency of heavy maintenance longer time implies a more expensive job (MRb) has increased Maintenance Planning March 2011 − www.mromanagement.com MRO Management 9 MROM_Mar11_digital.indd 9 07/03/2011 08:20 Airframes Data document (MPD) intervals to: A check 21 months, and D checks every six years, 1,000FH, C check 24 months (but not to exceed although it has now adopted the MRb/MPD 10,000FH), and D check eight years, explains programme with the exception of the C check bCA maintenance-engineering director Larry 10,000FH restriction. The German MRO performs Slate. After two D checks (D1 and D2), eight-year 12 747-400 D checks per year on a single line, inspections become six-year inspections for says D2 or D3 checks should require 40 to 45 relevant structures. days, and at the beginning of 2011 still had slots Ali points out that not all interval available in the middle of the year. improvements arose from MPD changes: “In Middle East maintenance provider El Al many cases, lead operators were supported Technical (EAT), whose parent airline group to analyse and increase their check intervals operates seven 747-400s (including one based on their own experience”. He says that freighter) with an average age of 10 years, the current 747-400 inspection schedule and has not adjusted its inspection schedule over escalation of individual intervals implies a 15% time, according to information provided by reduction in scheduled tasks over the life of maintenance-marketing manager Eli uziel, an aircraft and a corresponding reduction of aircraft overhaul-division production-service about 5% in hangar space demand. manager Moshe Tabib, maintenance-specifi- cation manager Shaul Peri, and aircraft-structure, Alternative approaches Interior, and non-destructive testing engineering Different operators or MRO providers may use manager Oren Jerasi. LHT confirms an industry trend for D checks to take place in Asia, where manhour rates are different schemes, according to a small random EAT has adopted C check intervals of much lower than elsewhere. It is the main source survey by MRO Management. For example, in 16,000FH (or 18 months – whichever comes of European C check capacity following AFI KLM E&M’s decision to drop such maintenance Europe, the Lufthansa Technik (LHT) schedule first) and D checks every 25,000FH (or 72 (photo: Lufthansa Technik) involved A checks every 700FH, C checks every months), and has performed about 10 D checks Engine services with the global wingspan Service soars with the Eagle. to reach anywhere you fly, day or night. Our more than 50 locations across the globe stand ready to provide dependable services that anticipate needs, create value and keep aircraft fl ying – anywhere, anytime. With more than 85 years of experience producing and maintaining dependable engines, Pratt & Whitney Global Service Partners combines the experience of an OEM with the fl exibility of an MRO, defi ning the service standard for all commercial engines – including our competitors’. Discover the OEMRO® advantage at pw.utc.com/OEMRO. It’s in our power.™ MAINTENANCE | REPAIR | OVERHAUL MROM_Mar11_digital.indd 10 07/03/2011 08:20 24290_GSP Global_MRO Management.indd 1 2/3/11 3:38 PM Client: Pratt & Whitney Ad Title: GSP Global Publication: MRO Management Trim: 406 mm x 145 mm • Bleed: ?? 412 mm x 148 mm (no bleed on top) Airframes – including one third-party contract for a foreign How is the boeing 747-800 expected to compare? carrier. The MRO schedules “approximately 15 days (around 13,000 hours)” for full C checks and 25 or 50 days (around 27,000 hours), respectively for partial or full D checks. This year’s slots are sold out and it is accepting enquiries for 2012. before the parent company grounded its fleet of one 747-300 and three -400s as an economy measure, the technical division of South African Airways (SAA) divided A check, 650FH-interval work into two separate maintenance jobs: the airframe check (CKA) plus weekly engine items, and the engine (photo: Boeing) check (CKE) plus weekly airframe items. C checks were performed every 6,500FH, or boeing concedes that since the new 747-800 (marketed as the 747-8) is a larger aircraft than 18 months, and D checks at a maximum of the current 747-400 (an extra 51 seats and an 18ft longer fuselage), its maintenance costs six-year intervals. would normally be expected to be higher. “However, due to system, structural, and SAA Technical has capacity for up to four maintenance-programme improvements, the airframe maintenance cost is expected to 747 D checks a year, with no current backlog. be 3% lower than that of the -400,” says boeing Commercial Airplanes maintenance- One 747-400 still in service was due for a economics director Khwaja Ali. “Technology improvements reduce cost by 5% and C check in March 2011and a D check in July maintenance programme by 3%. Size (weight and passengers) increases cost by 4% for [a] next year. Aircraft not in operation are subject net cost reduction of 3%”. to weekly checks and SAA has carried out Engine services with the global wingspan Service soars with the Eagle. to reach anywhere you fly, day or night. Our more than 50 locations across the globe stand ready to provide dependable services that anticipate needs, create value and keep aircraft fl ying – anywhere, anytime. With more than 85 years of experience producing and maintaining dependable engines, Pratt & Whitney Global Service Partners combines the experience of an OEM with the fl exibility of an MRO, defi ning the service standard for all commercial engines – including our competitors’. Discover the OEMRO® advantage at pw.utc.com/OEMRO. It’s in our power.™ MAINTENANCE | REPAIR | OVERHAUL MROM_Mar11_digital.indd 11 07/03/2011 08:20 24290_GSP Global_MRO Management.indd 1 2/3/11 3:38 PM Client: Pratt & Whitney Ad Title: GSP Global Publication: MRO Management Trim: 406 mm x 145 mm • Bleed: ?? 412 mm x 148 mm (no bleed on top) Airframes third-party work for Lufthansa, Saudi Arabia’s What’s your Powering improvement Kingdom Holding, Saudi Arabian Airlines and TAAG Angola Airline.