Forrest S. Petersen, US Navy X-15 Pilot No. 4.

courtesy Sheri McKay-Lowe collection

Petersen (in US Navy uniform) with McKay, Walker, and Armstrong.

courtesy Cathie Godwin collection

XLR99-RM-1 rocket engine test firing at Reaction Motors, Denville, New Jersey.

courtesy Wade Martin collection

North American rocket personnel at blockhouse wearing Chinese hats and gas masks.

courtesy Dave Stoddard collection

Early test flight of the X-15 using LR-11 rocket engines.

courtesy North American Aviation

Comparison of the LR-11 and LR-99 rocket engines used in the X-15 program.

courtesy Armstrong Flight Research Center

Twin LR-11 rocket engines installed on the X-15, providing 16,000 lbs of thrust.

courtesy author's collection

LR-11 rocket engine run at sunrise at the Propulsion System Test Stand.

courtesy TD Barnes collection

The XLR99-RM-1 rocket engine assembly line at the Reaction Motors plant in Denville, New Jersey.

courtesy Thiokol

LR-99 rocket engine test at PSTS.

courtesy Dave Stoddard collection

The business end of X-15 No. 1 with the 60,000 lb thrust LR-99 rocket engine.

courtesy author's collection

A rare photo of all four original primary pilots for the X-15: Scott Crossfield of North American Aviation, Joe Walker of NASA,

Robert White of the US Air Force, and Forrest Petersen of the US Navy.

courtesy author's collection

Forrest Petersen following an X-15 flight.

courtesy Tony Landis collection

X-15 No. 1 undergoes a test firing of the LR-99 in the engine test stand.

courtesy Tony Landis collection

Petersen gets the red carpet treatment after his promotion: 2-19-35 on 28 Sep. 1961.

courtesy Dave Stoddard collection

Petersen in X-15 No. 2 cockpit with emblem of his new rank: 2-19-35 on 28 Sep. 1961.

courtesy Dave Stoddard collection

Petersen meets with USAF pilots following flight: 2-19-35 on 28 Sep. 1961.

courtesy NASA Headquarters

Following the Collier Trophy ceremony White, Walker, and Petersen meet VP Johnson.

courtesy NASA Headquarters

Working on X-15 No. 1 to prepare for its return to Edwards following the Mud Lake emergency landing: 1-25-44 on 10 Jan. 1962.

courtesy Armstrong Flight Research Center

Removing the upper tail from X-15 No. 1 after emergency landing at Mud Dry Lake.

courtesy NASA Headquarters

Loading X-15 onto the flatbed after Petersen's emergency: 1-25-44 on 10 Jan. 1962.

courtesy NASA Headquarters

Loaded and ready to depart Mud Dry Lake.

courtesy NASA Headquarters

Trucking the X-15 overland from Mud Dry Lake back to Edwards.

courtesy Armstrong Flight Research Center

(above and below) Winding and narrow mountain roads were a hazard.

courtesy Ed Nice collection

Taking a rest break in Beatty, Nevada, on the way home to Edwards.

courtesy Armstrong Flight Research Center

Two vastly different modes of transportation.

courtesy Armstrong Flight Research Center

Arriving at the X-15 cockpit to help Petersen out: 2-19-35 on 28 Sep. 1961.

courtesy Edwards History Office

A B-52 salute after Petersen's highest and fastest flight: 2-19-35 on 28 Sep. 1961.

courtesy Armstrong Flight Research Center

The X-15s undergoing maintenance in the NASA hangar.

courtesy TD Barnes collection

Goofing around with Rushworth, McKay, Petersen, Walker, and Armstrong: Oct. 1960.

courtesy Grace Walker collection

Having fun with an X-15 pilot group portrait.

courtesy author's collection

More goofing around, later in the X-15 program.

courtesy author's collection