COVERSTORY After heavy maintenance, an aircraft usually must be flown to ensure that it was put back together properly. Check Flight Checkup FSF symposium focuses attention on functional check flight safety. BY MARK LACAGNINA xcitement and adventure are correctly after the airplane was taken This red flag prompted the industry not on the typical line pilot’s apart during heavy maintenance. to ask Flight Safety Foundation (FSF) agenda. Standard-rate turns, There is a bewildering variety of to organize an international meet- smooth power and configura- names for the types of ad hoc non- ing to discuss the risks and how they tionE changes, and staying comfortably revenue flights that aircraft operators can be reduced. “While exploring the within the “envelope” mark an airline perform, which include postmaintenance, issue with industry safety specialists, pilot’s professionalism. Sometimes, airworthiness, aircraft-acceptance and we found that there are not as many however, pilots are called upon to take end-of-lease check flights. However, a answers as there are questions, not aircraft to their limits, to demonstrate recent fatal accident and a rash of serious the least of which was how to define that normal and emergency systems incidents have made one thing clear: The the topic,” said Jim Burin, FSF direc- are working properly, or to determine risks involved in these flight activities are tor of technical programs. “Test flights if everything was put back together higher than in normal operations. are not performed by operators but 14 | FLIGHT SAFETY FOUNDATION | AEROSAFETYWORLD | MARCH 2011 COVERSTORY by manufacturers’ test pilots. We’re not talking — was that this question must be asked before about check flights, either, because check flights launching any functional check flight. involve aircrew evaluation.” “Flight checking of aircraft, particularly Ultimately, the term functional check flight older aircraft, often is driven by the mainte- was adopted by consensus of a steering team nance manual,” said keynote speaker David © Jonathan Rankin/Jetphotos.net formed by Burin of specialists from Airbus, Morgan, chief pilot and general manager for Boeing, Bombardier and Embraer. Air New Zealand. However, aircraft maintenance manu- Pivotal Question als (AMMs) often lack clarity, said Homero For the 275 aviation safety specialists who came Montandon, a test pilot in the Airworthiness from 41 countries to attend the FSF Functional Branch of ANAC, the Brazilian national civil Check Flight Symposium in Vancouver, Canada, aviation agency. “AMMs should be more specific Feb. 8–9, there were many other questions to about the necessity to perform check flights ponder: Are the crews who conduct such flights after maintenance,” he said. qualified to do so? What are the necessary Andre Tousignant, director of the Air Safety qualifications? How do you train crewmembers Investigation Office at Bombardier Aerospace, for functional check flights? Are simulators noted that few, if any, functional check flights adequate for the task? Are operators getting the are required by the AMMs for modern air- information they need from the manufactur- craft that have on-board troubleshooting and ers? Are they getting useful guidance from the fault-reporting systems. The AMM for the This A320 regulators? Do we need more regulations? Q400 requires only a trim check after an aileron crashed when the Do we need to perform functional check is replaced. The AMM for the CRJs requires crew lost control flights at all? either a flight check or a ground check after an while performing The resounding answer to that question — air-driven generator is repaired or replaced. “If a low-speed checks from the attendees and the speakers who repre- flight check is not required by the AMM, we see at low altitude. sented manufacturers, regulators and operators1 no need for it,” he said. © Nik French/Jetphotos.net WWW.FLIGHTSAFETY.ORG | AEROSAFETYWORLD | MARCH 2011 | 15 COVERSTORY Similarly, Joáo Carlos Braile and Fab- following the crash of an Airbus A320 in gray hair; with other airlines, it sets rízio Sabioni Lourenço, who coordinate Perpignan, France, on Nov. 27, 2008. The with those with the most education.” flight test activities at Embraer, noted that accident occurred during an end-of-lease Customer acceptance flight check- the AMM for the Embraer 145 requires demonstration flight pending the return lists, which usually are provided by a flight check for data acquisition, only. of the aircraft to Air New Zealand by XL manufacturers with the sale of a new There are no requirements for check Airways (ASW, 11/10, p. 22). aircraft, typically are adapted by opera- flights in the 170/190 AMMs, they said. The official investigation by the tors for use in end-of-lease demonstra- Unnecessary flight testing must be French Bureau d’Enquêtes et d’Analyses tion flights and other types of functional avoided, said Gary Meiser, chief pilot of found that the flight crew was not aware check flights. “Many operators are production flight test at Boeing Commer- that the angle-of-attack sensors were conducting functional check flights with cial Airplanes. “We need to eliminate test- blocked by ice — they lost control of checklists that are out of date,” Morgan ing for testing’s sake,” he said. “We need the A320 while performing low-speed said. “They might not apply to changes to ask ourselves: Does it really need to be checks at low altitude. Among the fac- made per service bulletins, for exam- flown? Can it be done on the ground?” tors that contributed to the accident, ple.” He called for more support from Exemplifying one of the gray areas which killed all seven people aboard manufacturers in keeping checklists associated with this topic, the an- the aircraft, was the flight crew’s lack of up-to-date. swers to Meiser’s questions might be training and experience in performing The regulatory framework for func- maybe and maybe not, according to Sel functional check flights, and their inad- tional check flights, too, is “less than Laughter, flight test manager for United equate coordination during the flight. optimal,” he said. “Regulatory interven- Airlines. Noting that United checks During its in-house investiga- tion could be quite useful. We need a backup systems during postmainte- tion, Air New Zealand discovered that more effective and consistent regulato- nance flights, Laughter said, “A lot of several other airlines were performing ry framework with a clearly defined set times, they’ll check OK in the hangar similar end-of-lease demonstration of rules to cover all nonrevenue flights.” but not in the air.” flights. “We found that the processes Lessons from the Perpignan ac- for these types of flights tend to be cident report and the airline’s in-house Hard Lessons handed down from one chief test pilot investigation prompted Air New Zea- In his keynote address, David Morgan to another,” Morgan said. “With some land to “take a policy decision not to recounted lessons learned during Air airlines, the responsibility for these expose our crews to what we consider New Zealand’s in-house investigation flights sets with those with the most unacceptable risk when conducting end-of-lease and other ad hoc flights,” Morgan said. That policy subsequently was chal- lenged by a set of end-of-lease dem- onstration procedures demanded by a leasing company. The airline found that some of the procedures posed unnec- essary risk, but the leasing company contended that the procedures had served them well, so why change them? Although some compromises were reached, Air New Zealand refused to perform several systems checks that it Vancouver, site of the believed could be performed adequate- FSF Functional Check ly on the ground. “Aircraft systems or Flight Symposium. components should only be checked in the air if they cannot be checked on the Mark Lacagnina ground,” Morgan said. 16 | FLIGHT SAFETY FOUNDATION | AEROSAFETYWORLD | MARCH 2011 COVERSTORY operating weights during functional check flights, resulting in “handling qualities that may be different than what we are used to,” said Harry Nelson, an experimental test pilot for Airbus. ‘Hard Limits’ Several speakers emphasized the need for painstaking preparation for func- tional check flights. Among the factors to be considered are the time of day, weather conditions and the airspace in which the flight will be conducted. Advance coordination with air traf- fic control (ATC) is important. “You must consider ATC as an integral part Mark Lacagnina of a successful test flight,” said Steve Although the airline adhered to its (Accident Prevention, 9/97). However, Smith, manager of flight technical ser- safety policy, the leasing company did the system failed to activate, and the vices for Cathay Pacific Airlines. not relent. “The checks we refused to aircraft stalled at a slightly higher-than- “Maintenance partnership is critical,” carry out were subsequently imposed expected airspeed, possibly because said Boeing’s Meiser. “There must be on the delivery crew from the next of ice accumulation and/or control open and honest dialogue.” airline,” Morgan noted. misrigging, said the report by the U.S. Detailed briefings between flight National Transportation Safety Board crews and maintenance teams should Simulator Infidelity (NTSB). be conducted before and after a func- Morgan said that the in-house inves- The pilot flying applied full aft con- tional check flight. Before flight, the tigation also led Air New Zealand to trol pressure when the DC-8 suddenly crew should review the emergency question whether flight simulators pitched nose-down. The aircraft then procedures for each system and compo- realistically replicate the flight charac- descended rapidly in a full stall and nent that was involved in maintenance, teristics of an airplane flown close to or struck terrain near Narrows, Virginia, said Bombardier’s Tousignant. beyond the edge of its flight envelope.