Refle tions

First Flights of the ATF Prototypes Refle tions First Flights of the ATF Prototypes YF-22 Dave Ferguson Tom Morgenfeld YF-23 Paul Metz Jim Sandberg Dave Paul

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ATF Chronology Study Contracts since the late 1970’s 01 Oct 1986 Contract Awards LOCKHEED/ GENERAL DYNAMICS NORTHROP/McDONNELL DOUGLAS Pratt & Whitney General Electric Apr 1991 Downselects

THE SKUNKS

YF -22 “Lightnings”

YF-23 “Ghosts”

ATF Chronology Study Contracts since the late 1970’s 01 Oct 1986 Contract Awards 27 Aug 1990 YF-23 #1 (PW) 29 Sep “ YF-22 #1 (GE) 26 Oct “ YF-23 #2 (GE) 30 Oct “ YF-22 #2 (PW) Apr 1991 Downselects

YF-23 PAV 1 27 AUG 1990 PAUL METZ

YF-23 PAV-1 First Flight Scrupulous TEAM preparation Off-the-shelf ain’t if it’s changed The magic works, but the plumbing don’t

Dave Ferguson YF-22 Chief Test Pilot YF-22 SHIP # 1 29 SEPT 1990 Dave Ferguson YF-22 Chief Test Pilot

YF-22 Ship # 1 First Flight Schedule imperatives are REAL. PLAN to be flexible Flight/Ground Idle… STATE changes The First Flight’s not done ‘til the test cards are.

Jim Sandberg YF-23 Project Pilot The YF-23 Dem-Val Program YF-23 PAV 2 26 OCT 1990 Jim Sandberg YF-23 Project Pilot

YF-23 PAV-2 First Flight Been there, done that… Darryl always used to say… The First Flight’s not done ‘til the test cards are.

Been there, done that, but…… Lesson Learned Been there, done that, but…… Always beware of taking off in the opposite direction on a single runway on a different frequency than all other traffic. 17

Lesson Learned On Tower Freq: “Cobra 12, Cleared for touch and go” On Test Freq: “Ghost 2, Cleared for takeoff” T-38 Training Flight F-16 Safety Chase The first flight of GE-powered PAV-2 was indeed the first flight of this airplane/engine combination. But I approached it with high confidence since Paul had already proven that the YF-23 airplane would fly and Ferg had already proven that the GE engine would fly. But the AFFTC Safety Review Board determined that it would be best to stick with the original First Flight plans and do the first flight takeoff on Edwards runway 04, into the lakebed and opposite traffic. These plans also called for a thoroughly briefed, dedicated tower controller on our test frequency so that we would not use the tower frequency for our test talking. We briefed it twice, and practiced it once with surrogate aircraft, just like we did for Paul’s first flight but when the big day came, it just didn’t turn out like we expected… Roll Tape F-15 Photo Chase YF-23 #2 18

ROLL YF-23 TAKEOFF VIDEO HERE ?

Darryl always used to say… Lesson Learned Darryl always used to say… EXPECT to have landing gear difficulties on any first flight The theme of the Flight test Safety Workshop in Dayton Ohio in 2000? was on First Flights and there was about 17? presentations on first flights throughout the years and, listening to them, I was struck with how many of those seminal events (12? 14?) were marred by difficulties with landing gear. Well, Ferg’s airplane had fits getting the gear up, and Paul’s first flight was cut short by a landing gear that sagged after it was up and locked, and I don’t know about Trees’ gear but I do know about mine! Roll Tape 20

YF-23 Landing Gear Video Here?

The First Flight’s not done ‘til the test cards are… Lesson Learned The First Flight’s not done ‘til the test cards are… 23

The “Apollo 13” Phenomenon Gausian Shaping One flight 5 of PAV-2, chase noticed a high pressure stream of fluid coming from the botttom of the airplane as it climbed through 20,000’. As he moved in for a closer look, the mission control room commanded “Descend Immediately and LAND!” Unbenownst to the test pilots, the fuel tanks had overpressurized to more than 150% of their design limits. Had the tanks ruptured, it could have been catastrophic. The airplane was impounded and the fuel system was torn apart to determine why the tanks had overpressurized. Nothing was found. When reassembling the fuel system, the crew chief was installing a 5/16” pressure sense line that ran through the bottom of the fuselage and sensed ambient pressure to give the fuel system a pressure reference to attain a 5 psi differential over the tanks. By chance he happened to run a wire up through the sense tube and found it blocked by a piece of silicone RTV used to seal the sense line mounting flange to the fuselage. The silicone had trapped airfield level pressure in the line and, as the YF-23 went to altitude, the fuel tank pressure was held at a constant 5 psi to the airfield but an ever increasing differential to the real ambient pressure on the tank. The bottom line was that some sharp mission control room engineers were watching the telemetered absolute tank pressure, couldn’t explain it (this can’t be happening!!”) and were bold enough to command an abort. It was a simple problem which led to unexplained and unplanned events which fall in that category of “you can’t think of everything so be suspicious and cautious of everything”.

YF-22 SHIP #2 30 OCT 1990 Tom Morgenfeld

YF-22 Ship # 2 First Flight Off-the-shelf ain’t if it’s changed Scrupulous TEAM preparation First Flight CREWS The First Flight’s not done ‘til the test cards are.

SLEEPING WITH THE ENEMY

How it Went (Dem/Val Stats) YF-22 PAV-1 (GE YF120) 29 Sep to 28 Dec 90 Sorties: 43 Hours:52.8 PAV-2 (PW YF120) 30 Oct to 28 Dec 90 Sorties: 31 Hours: 38.8 Total Sorties: 74 Hours: 91.6 YF-23 PAV-1 (PW YF119) 27 Aug to 30 Nov 90 Sorties: 34 Hours:44.4 PAV-2 (GE YF120) 26 Oct to 15 Dec 90 Sorties: 16 Hours: 21.4 Total Sorties: 50 Hours: 65.8

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