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Boeing's 787 Dreamliner Completes Successful First Flight
December 16, 2009
5 Min Read
In spite of clouds, rain, ice and turbulence that wouldnormally scrub a First Flight, Boeingdecided to make a statement about their confidence in the 787 - a statementdesigned to defuse the perception that the Dreamliner program is in trouble andlikely to stay that way.
Pending a thorough review of the engineering data, itappears they were successful and then some.
From the moment of liftoff from Paine Field, the airport adjacent to the sprawling Boeing factoryin Everett, WA, until the picture perfect landing threehours and four minutes later, the flight was anomaly free.
"We encountered icing and turbulence - which weren't on thetask list - but there were no problems," according to Randy Neville,Engineering TestPilot for the 787 program.
Mike Carriker, chief pilot for the program, said "Theengineers said we'd have a great airplane and we do."
The first Dreamlinerto fly has three names: ZA001, the inventory designator, AP1 - short forAirplane Number 1, and N787BA, the FAA registration number. It will never bedelivered to a customer and is one of six aircraft dedicated to the testingprogram.
AP1 has no passenger seats or any interior finishing.Instead, the payload consists of rack after rack of test equipment interfacedto provide over 1,000 telemetry channels of data. At the other end of the data-link,engineers watch in real time and archive all data for later examination.
The telemetry system, extensive though it may be, was onlyoperating at 1/10th capacity during the First Flight. Later flightswill see more channels of data collected as the Dreamliner goes through a ninemonth certification process that culminates with the Federal AviationAdministration's (FAA) permission to build and sell the airliner.
With two T-33 military jet trainers flying chase, Boeing 1,the Dreamliner's Air Traffic Control call-sign, lifted off Paine Field's runway34 Left at 10:29 PST on Tuesday, Dec. 15, 2009. And for the next three hours,it flew a zigzag path above the Straits of Juan de Fuca at altitudes rangingfrom 2,500 to 13,000 ft as the First Flight objectives were ticked off the tasklist one by one.
Seen on a radar screen, the path resembled the flight of aHoneybee foraging for nectar but it was data that Carriker and Neville wereseeking.
The most critical data were validations of the aerodynamicqualities the designer's equations had predicted. Especially important weretests for any sign of flutter. (Aerodynamic flutter is a harmonic conditionthat appears at specific speeds and/or flight control settings. It can destroythe surface in question and result in the loss of the aircraft.)
Also important were the low speed stability tests sincedemons lurking there can cause all sorts of handling problems. For instance, anairplane that's unstable at low speeds will be a handful to take off and land.It would also be an aircraft that few test pilots would want to be in when thehigh speed stability predictions are validated.
For most of the flight, the landing gear was extended andthe flaps were left set at the 20 degree take-off position. Later, the gear wascycled and the flaps were extended to 30 degrees which more closelyapproximated the landing position.
Airspeed was kept intentionally slow at approximately 160knots and rates of climb and descent were both kept at or below 1,000 ft/min.In addition, bank angles and pitch changes were held to low values to provide abase line of stress levels for later testing.
Engine operation, flight instrumentation and criticalsystems all performed as predicted according to the flight crew who said that theairplane appeared to have no bad habits.
Flight control harmony - the way that various controls worktogether - particularly impressed Carriker. "I told the engineering folks backat flight ops that they had gotten it just right," he said.
Since the 787 is a Fly-by-Wireairplane, his accolades also meant that artificially generated forcefeedback present in the controls provided the "feel" of a conventional airplanebut with the precision of computer assisted flight controls.
Neville echoed Carriker's assessment: "It brings back thejoy of aviation because the airplane flies beautifully. It became second nature(to hand fly) very quickly," he said. Both Neville and Carriker think theairplane flies better then the simulator.
A neutral observer expects company test pilots to not dwellon any shortcomings but reporters asked more then once if there were anysurprises or problems and both pilots gave straight forward answers that leftvery little wiggle room.
Neville said, "No surprises - in spite of very highbenchmarks. It responded just as we expected."
"We've shown that the airplane flies today and in the nextnine months we'll show it meets all the design goals. We had a great day."Carriker commented.
The Path toCertification
Now the tedious work of testing the airplane begins.Exploration of the entire flight envelope will require most of 2010 and themajority of that work will be done by test pilots who are also engineers. Alongthe way they'll be required to fly precisely, holding airspeeds and altitudeswithin limits far tighter than an airline pilot is required to exhibit.
Being engineers, the public will view them as automatonsprogrammed by the great engineer in the sky to do a job without emotion. Butonce and awhile, an engineer will break free and experience something like whatMike Carriker did shortly after taking off on the First Flight:
"We climbed to 2500 feet initially and stayed below theclouds until we were out over The Straits of Juan de Fuca and then we startedclimbing. At 7,000 we popped out and there was the snow capped Olympics framedin the left window. I'll never forget that sight the rest of my life."
John Loughmiller is an electrical engineer, commercial pilot, flight instructor and a lead safety team representative for the FAA.
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