Operation CASTLE's 15 MT Bravo early fireball with Compton Effect lightning, March 1, 1954

Friday, February 7, 2014

Section 1, Operation HARDTACK Military Effects Studies (1958): High Altitude

Here are some early color test experiments from random frame comparisons of scenes (before and after):

Low resolution color test

DASA was the 1959 successor of the Armed Forces Special Weapons Project (AFSWP). Today's version of this military agency's functions is the Defense Threat Reduction Agency (DTRA).

A Convair RB-36 Peacemaker.

A comparison rendering with uniformity makes more sense. The texture of the background upper sky suggests color instead of blackness.

 A P2V-5F Neptune patrol aircraft

Aircraft were used as camera platforms for recording fireball data. The black camera to the left was a 70 mm Mitchell. The large grey camera was a Wollensak Fastax 35 mm High Speed, capable of 5000 fps, but operated at 2000 fps. Cameras used: 35 mm Fastax FF-1, 35 mm Fastax FF-2, 70 mm Maurer M-4, 70 mm Hulcher H-10, 70 mm Streak STR-4, and 24 fps Mitchell.

An Air Force technician checked this recording instrument during fireball studies aboard a gigantic Convair RB36H Peacemaker aerial platform.

Aerial data capture platforms were packed with scientific equipment during HARDTACK I.

The YUCCA test's helium balloon assembly before deployment. It was launched from the USS Boxer (CV-21) carrier between Enewetak and Bikini Atolls.

Recalling an earlier test, on 6 April, 1955, a B-36H dropped the 3.2 kt HA (high altitude) device (in a Mk-5 ballistic case), detonating at 36,620 feet/11.2 km, forming a rapidly rising torus.

Nitrogen dioxide (NO2) formed in the fireball in the low-density atmosphere, created a pale, reddish-brown tint.

A 1957 Chevrolet 3100 truck painted brown for government service, including the white ID number on the bumper.

TEAK and ORANGE warhead payloads were launched by Redstone missiles from Johnston Island, under the direction of Wernher von Braun. Both tests comprised Operation NEWSREEL. Each W39 warhead test produced 3.8 MT yield. Here a fireball environment probe was mounted at the base of a rocket.  

From the Operation HARDTACK 1958 Defense Nuclear Agency report:

The two scientific team members assembled the nosecone onto a high altitude scientific probe of the type placed closest to the TEAK and ORANGE bursts. Carried along the bases of the Redstone launch missiles, and later jettisoned at the targeted altitudes, these instruments recorded thermonuclear effects. Momentum reaction gauges, radiant energy intensity, and ablation plugs (for effects of intense X-rays on materials) were part of the structural materials pod.

Fireball sizes reached 10 mi/16 km across in the visible spectrum, and 40 mi/64 km wide in the infrared spectrum.

Macular and retinal eyeburn studies were important for designing defenses against nuclear flashes. Nuclear fireballs are 50x the intensity of our Sun's photosphere, per unit surface area.

A Redstone missile test immediately before launch ignition:

The TEAK burst from 50 mi/80 km below, as filmed from the Johnston Island launch site. The blue quickly darkened, as a first orange shell rapidly expanded into a red color, covering much of the sky.

That trail from the bottom left was an exhaust trail from a rocket that launched a scientific probe into the fireball region. 

Ouch at those discontinuities in the sky, and some cross-coupling of color in the tower, that require more labor. The gaps of continuity are caused by the sweeping color bar artifacts from the Betacam SP to VHS transcription:

Evidence of Redstone launch preparations, appearing to be fueling, is seen the oxygen vapor emission.

A new trial test increased uniformity in sky color (above)

The B-36's outboard jet engines were only used for takeoff and fast climbing, to conserve fuel consumption during Strategic Air Command missions frequently lasting 40 hours:

The giant B-36 was famously described by USAF Lieutenant General James Edmundson:

"Well, the B-36 really wasn't much fun to fly. It's a gigantic thing. They used to say it was like sitting on your front porch and flying your house around. It was big on the outside and small on the inside. Very cramped for the crews. And the missions were long."
More:  Emundson interview 
The XB-36, here (above) a1948 prototype, dwarfed the United States' first strategic bomber, the B-29/50. Crews entered in front and rear ladders 50 yards/45 meters apart. 

Courtesy of Wikipedia.

Thursday, February 6, 2014

Section 2, Operation HARDTACK Military Effects Studies (1958): High Altitude

Technicians readied a remote camera boom for technical photography.

Cameras were vital where people couldn't be during atmospheric nuclear tests, especially for safety reasons.

Lessons were learned during the BRAVO shot in March 1954, that caused massive damage the Eninman Island A base at Bikini Atoll, over 12 miles (19 km) away from the device B.

Bracers were constructed for the 29 June, 1958, 8.9 MT OAK test, to prevent buildings from collapsing. Power sources were sandbagged against tsunami flooding effects:

Operation HARDTACK I 1958
DNA 6038F
Blast gauge:


 MV Acania was part of a science project measuring signal attenuation through high altitude bursts.

MV Acania later served again during the DOMINIC I Fishbowl tests in 1962.

Radar trailers, like this suspected (Signal Corps Radio) SCR-584 Mod II microwave system, were everywhere during HARDTACK I. The 584 was developed by MIT during WW II, and subsequently.

Was this trailer originally brown or green? Input is welcomed.

This materials test pod was subjected to a 3.8 megaton thermonuclear environment at high altitude.

Both scenes were B&W still photos of this pod. Part of the photographer's label is to the bottom right of the lower image.

Darkening to the right of the pod, along  the transverse (90° to the length) axis of its casing, was caused by intense X-ray burns at 23,000 feet (7 km) from the warhead.

TEAK was fired at 10:50 PM, 1 August.

ORANGE took place at 10:30 PM local Johnston Island time, 12 August.

Operation HARDTACK I 1958
DNA 6038F

The (above) probe was likely a lower altitude probe, farther from the warhead's detonation altitude. A clue is an apparent lack of X-ray surface scorching, unless an overexposure masked it. Nevertheless the scientist used only light, disposable handling gloves..

Operation HARDTACK I 1958
DNA 6038F

Free neutron absorption from the W-39 thermonuclear warhead of the TEAK test caused this probe to become radioactive.

Pods were sequentially dropped in the pattern of this diagram.

Instrument pods at the base of a Redstone missile before takeoff

Considering that these missiles also lifted the NASA Mercury space capsules less than 3 years later, the small diameter of the Redstone was barely large enough to fit a capsule that could carry an astronaut.

Technicians secured the instrument pods to the Redstone.

Among the data collected by the pods were exposure readings at various distances from the weapons explosions:

Lethal radiation exposure rates span enormous distances high above the Earth, because of the low absorptivity of the low density atmosphere. Readings in this diagram scale to millirems per microsecond.

1 μ sec = 1 millionth of a second

Those nasty yellow lines in the left image scan vertically through the scene. Removing them is a real problem.

The bangs from these 3.8 megaton (each) high altitude explosions were extremely loud at the island launch site, yet originated from the thin air above.
.1 PSI = 150 dBSPL (decibels sound pressure level)
.18 PSI = 155 dBSPL

Rabbits were mounted in surface and airborne stations, for flash studies on the eye, a pressing concern for the military during that time.

 A land test over sand is seen above, while the lower image was located on a ship.

Those instruments to the upper right were photocell sensors for measurements of overall exposure at this station:

MATS (Military Air Transport Service) delivered much of the airborne shipments of cargo and test animals to the staging sites.

For TEAK, these stations were located:
  1. Johnston Island
  2. USS De Haven (DD-727), 70 nautical miles (130 km) from Johnston Island
  3. USS Hitchiti (ATF-103), 350 nmi (649 km) away from J.I.
  4. 2 B-36s flying at 15 000 feet (4.57 km), 350 nmi (649) km from surface zero
  1. USS Boxer (CVS-21), 50 nmi (93 km) from Johnston Island
  2. USS Epperson (DDE-719), 65 nmi (120 km) from J.I.
  3. USS De Haven (DD-727), 120 nmi (222 km) from J.I.
  4. 1 C-97 aircraft, 205 nmi (380 km), at 24 000 feet (7.31 km) from J.I.
Remarkably, Johnston Island was excluded from ORANGE surface animal testing sites, since the island reached 500 °F (260 °C) for some seconds, therefore requiring remaining brush and other combustibles to be removed before the test.

The doctor used an opthalscope to examine each eye.

A close-up view of the commander:

Each rabbit was then carefully photographed for weapon optical effects on the retina and macula. 

This was a remarkably messy cut (above), with so much color-bleeding and hotspots.

More work needs to be done to recover the color of the uniform.

Photographic sequence, starting with the eye open at the camera flash:

The blink reaction:

Scientific data for analysis were central to the objectives of all nuclear tests. TEAK, at approximately twice the altitude burst height, had a very short pulse lasting milliseconds, due to the very thin atmosphere at 250 000 feet (76 km). There was little atmosphere to support a fireball.

TEAK from an aircraft near Johnston Island:

The image below needs another run, to turn the grey sky between the ground the cloud base to a blue color.

TEAK's 3.8 megaton W39 device burst at 250, 000 feet/50 miles (80 km) above the Johnston Island launch pad, 1 August, 1958. Both NEWSREEL tests were near midnight. TEAK's firing was under heavy cloudcover with some openings to the sky above. The flight time was 3 minutes.

A spectacular display of TEAK was observed from the Hawaiian Islands, 700 nmi (1,297 km) away.

The USS Boxer launched the YUCCA test balloon from its stern while maneuvering to keep the relative air motion on the deck to less 10 knots.

A Sikorsky H-34 helicopter was parked to the bottom right.

YUCCA's 1.7 kiloton W25 nuclear device was lofted inside this casing, with a long trail of radar tracking reflectors and data telemetry instruments hanging below it. In all, the entire balloon and bundled instrument package was 80 feet (24.4 m) long at launch. It was released at 11:25 local time.

The W25 device detonated at 82, 250 feet/16.3 miles (26.2 km) altitude, 28 May, 1958, at 14:40.


 The YUCCA cloud sequence improved (above) over its original appearance:

From Operation HARDTACK I 1958, DNA 6038F: