Time of firing: 0555 MST
    Agency: Applied Physics Laboratory, Johns Hopkins University
    Altitude: 99.9 miles

UPPER AIR INSTRUMENTS

    Cosmic radiation: Single Geiger counter in nose extension. Four pulse ionization
        chambers (APL)
    Solar radiation: Ultraviolet solar spectrograph (APL)
    High altitude photography: K25 camera

DATA RECOVERY INSTRUMENTS

    Telemeter: NRL PXTA-501, 23-channel PPM-AM system
    Physical recovery: Warhead blowoff by radio command

BALLISTIC INSTRUMENTS

    Firing Range
        Theodolites: Two Mitchell and eight Askania stations
        Cameras: Two ballistic and three Bowen-Knapp stations
        Telescopes: Two stations
        Radar: Two modified S-band stations
        Doppler: Four stations

    Airborne
        Beacon: AN/APN-55 S-band transponder
        Doppler: Dovap transceiver
        Radio Cutoff: AN/ARW-17 FM control receiver for command blowoff and cutoff
        Aspect: Two gyroscopes

ROCKET INFORMATION

    Unfueled rocket weight: 8533 lb
    Unfueled rocket C. G.: 226.2 in.
    Gross weight at takeoff: 27,023 lb

ROCKET PERFORMANCE

    Firing angle: 1.5 degrees
    Program angle: Approximately one degree
    Time to burnout: 62.5 sec
    Velocity at burnout: 4962 ft/sec
    Altitude at burnout: 119,800 ft
    Time to zenith: 224.5 sec
    Altitude at zenith: 99.9 miles
    Time to tail blowoff: 361 sec
    Altitude at tail blowoff: 239,000 ft
    Flight duration: 361 sec
    Impact coordinates: Four mi. west, 200 yd south of launcher

BALLISTIC DATA

    Theodolites: Mitchell - trajectory data from 0 to 63.62 sec, Askania - trajectory
        data from 0 to 73.25 sec
    Cameras: Bowen-Knapp - records for first 2000 ft, ballistic - images 0 to 62.5 sec
    Telescopes: Very good tracking
    Radar: Beacon intermittent throughout flight, strong at summit; complete tracking
        from one radar from 0 to 300 sec
    Doppler: Excellent signals at all stations with numerous interruptions
    Impact location: Visual and ground search

EXPERIMENTAL DATA

    Ultraviolet spectrum obtained to 2600A. Burst producing component of cosmic rays
        measured up to 160 km. Counting rate rose to 49/sec at 19.8 km, then rate fell
        off, reaching plateau from about 55 km to 161 km with average rate of 22.4/sec.
        Primary flux 0.12 particle/sec/cm²/steradian

COMMENTS

    Rocket modifications: Extension at nose tip to house Geiger counter (Bakelite
        cylinder)
    Rocket performance: Rocket inclined 1.5 degrees north on launcher. Trajectory
        angle near vertical, program was not introduced

REPORT AND PAPERS

    "Exploratory Cosmic Ray Observations at High Altitudes by Means of Rockets,"
        J. A. Van Allen, Sky and Telescope 7:171 (1948)
    "Cosmic-Ray Bursts in the Upper Atmosphere," H. E. Tatel and J. A Van Allen,
        Phys. Rev. 73:87 (1948)
    "Synopsis of Ballistic Measurements of the A4 Rockets Launched from November
        1946 to July 1947," H. P. Hitchcock, Report No. 695, BRL-APG, April 1949
    "The Cosmic-Ray Counting Rate of a Single Geiger Counter from Ground Level to
        161 Kilometers Altitude," J. A. Van Allen and H. E. Tatel, Phys. Rev. 73:245
        (1948)
    "The Ultraviolet Spectrum of the Sun from V-2 Rockets." John J. Hopfield and
        Harold E. Clearman, Jr., Phys. Rev. 73:877 (1948)
    "The Cosmic-Ray Intensity Above the Atmosphere," A. V. Gangnes, J. F. Jenkins, Jr.
        and J. A. Van Allen, Phys. Rev. 75:57 (1949)