On January 19, 1967, a U.S. Air Force KC-135 Stratotanker, en route from Hickam Air Force Base, Hawaii, with nine passengers and crew, disappears from radio and radar contact while on landing approach to Fairchild Air Force Base in Spokane County. The following day, two searchers on snowcats will find the wreckage of the aircraft scattered on semi-forested Linder Ridge approximately two miles southeast of Mount Spokane. There are no survivors. The accident nearly duplicates the crash of a KC-135 into Mount Kit Carson in September 1962, killing 44 airmen, the worst aviation disaster in the history of Spokane County.
The Boeing KC-135 Stratotanker, a military variant of the Boeing 367-80 (known as the Dash-80), is the only jet aircraft designed specifically for aerial refueling missions. It is a large aircraft, 136 feet long with a wingspan of 130 feet. At a cruising speed of 552 m.p.h., the plane is capable of carrying 31,200 gallons of extra jet fuel approximately 5,000 miles. Introduced in 1956, it replaced the propeller-driven Boeing KC-97 Stratofreighter which was too slow for jet combat aircraft. For routine aerial refueling operations, the KC-135 Stratotanker carries a crew of four consisting of two pilots, one navigator and one refueling-boom operator.
A Routine Flight
At noon on Thursday, January 19, 1967, Air Force KC-135, No. 56-3613, assigned to the 92nd Strategic Aerospace Wing, 43rd Air Refueling Squadron, Fairchild Air Force Base (AFB), departed Hickham AFB, Oahu, Hawaii, for a six-hour flight to Spokane, Washington. The tanker was escorting a group of Air Force McDonald-Douglas F-4C Phantom jet-fighters, with a ferry range of 1,403 miles, from Hawaii, 2,680 miles to the U. S. mainland. In addition to the four-man crew, the aircraft was transporting five airmen from Fairchild.
At approximately 6:00 p.m., the KC-135 was flying eastbound toward Spokane and was in radio contact with the Radar Approach Control Center (RAPCON) at Fairchild AFB. The pilot, Captain Billy E. Cammack, was directed to hold position, awaiting the landing of another KC-135, then given the go-ahead to enter a designated approach pattern and descend for landing. This routine approach maneuver takes the aircraft in a wide circle over Mount Spokane State Park at 14,000 feet, then on a line between Mount Spokane (5,883 feet) and Mount Kit Carson (5,282 feet), and over Mead at approximately 8,000 feet. The aircraft, now on final approach for Fairchild AFB, gradually descends over Spokane, onto the airfield.
Missing in High Winds and Heavy Snows
At 6:09 p.m., Captain Cammack reported to RAPCON he was at 14,000 feet and entering the approach lane for Fairchild when the aircraft vanished from the radar screen and radio contact was broken. Besides being night, weather conditions in the Spokane area were extreme, with high winds, heavy snow, a low cloud cover and limited visibility, requiring pilots to fly entirely by instrument flight rules (IFR) and land via an instrument landing systems (ILS) approach. The area surrounding Mount Spokane was immediately pinpointed as the probable crash site.
The first place search teams headed for was Mount Kit Carson, where a KC-135 had crashed on September 10, 1962, killing 44 airmen. Volunteers from the Spokane Snowmobile Association set out from the Mount Spokane Ski Lodge on trails toward Mount Kit Carson, searching for signs of the downed aircraft. Washington State Patrolman Clyde Singleton drove to the earlier crash site in a borrowed four-wheel drive vehicle, but found nothing.
The Mount Spokane Ski Patrol planned a systematic search of the general area by skiing down the slopes in patterns, attempting to cover as much ground as possible. But, after further analysis of the radar data, Air Force officials decided the KC-135 may have been blown off course and went down east of Mount Spokane. Search efforts were shifted toward the Idaho border and a field command post was established near Twin Lakes, Idaho, to coordinate activities. Search and rescue workers, braving blizzard conditions, hunted for the missing tanker throughout the night, without success.
Recovering Wreckage and Bodies
Finally, at about 9:00 a.m. on Friday, January 20, 1967, Gerald L. “Jerry” Deitz and Del Kerr, two snowcat drivers from Coeur d’Alene, Idaho, found the wreckage of the missing KC-135. The two men had been operating in the vicinity of Shadow Mountain (4,875 feet) when they spotted an area of burned trees on a distant slope. After an hour of searching, they finally found the bulk of the wreckage near the top of Linder Ridge (4,856 feet), approximately one-quarter mile north of Quartz Mountain (5,180 feet), in three feet of fresh snow. All that was left of the tanker was the tail section, sitting upright among the scrub pine trees, and a burned-out portion of the fuselage. The remainder of the large aircraft was in bits and pieces, scattered over the steep, semi-forested hillside. The bodies of four airmen were discovered laying in the snow; the other five bodies were inside the section of fuselage.
Throughout Friday morning, men from Fairchild’s Air Force Survival School worked to recover the bodies and by afternoon Air Force accident investigators were at the crash site. Colonel William Culbertson, vice-wing commander of the Strategic Air Command’s 93rd Bombardment Wing, Castle AFB, Merced, California, had convened a 13-member investigation board, made up of Air Force and civilian aviation specialists from other SAC bases, to begin a formal inquiry into the cause of the accident. Their first task, however, was to find and remove any classified equipment and documents from the wreckage.
The Air Force established a command post one-half mile down from the Mount Spokane Ski Lodge and some 50 persons were sent to the crash area to aid in the investigation. The assemblage included Air Police to keep away curious spectators and mess cooks with a field kitchen. The next three days were spent hunting for pieces of the tanker, which was scattered over 400 square yards of snow-covered hillside.
Since the KC-135 wasn’t equipped with a flight-data recorder (known as the “black box”) like commercial aircraft, the investigation would center around radio transmissions between the air traffic controller and the pilot, the aircraft’s maintenance records and whatever the investigators could discover from minutely examining pieces of twisted wreckage. Of particular interest were the aircraft’s flight instruments, if they could be found, and the jet engines.
Investigating the Cause
A study of the recorded data and audio tapes between Fairchild AFB and the KC-135 determined neither air traffic controllers nor the RAPCON system was at fault. The pilot was in the correct approach lane at a reported altitude of 14,000 feet, well above the minimum safety altitude for that area, when Fairchild lost radar contact with the tanker.
Winds over the mountainous area were reported to be in excess of 100 m.p.h. Although there was considerable air turbulence, it was well within the safety margins established by SAC. Lieutenant Colonel Stanley Ratto, commander of the 92nd Air Refueling Squadron, flew the exact same route in a KC-135, under the instruction of RAPCON, minutes before Captain Cammack’s tanker crashed, and had landed safely.
On Sunday, January 22, 1967, a period of clear weather allowed investigators to photograph the crash scene from the air. The pictures helped determine the direction and angle of the aircraft when it hit the hillside. The tanker would have cleared Linder Ridge, if it had been flying just 200 feet higher, but some unidentified problem could have caused the tanker to crash elsewhere.
The Accident Investigation Board wanted to determine why the KC-135, reportedly flying at altitude of 14,000 feet, was below 5,000 feet when it entered the approach lane for a landing at the airfield. Captain Cammack, a 12-year veteran of the Air Force, was described by his supervisors as a very capable pilot. The 43rd Air Refueling Wing had been reassigned from Larson AFB (now Grant County Airport) in Moses Lake, to the 92nd Strategic Aerospace Wing at Fairchild AFB on April 2, 1966, but Cammack had flown the approach route numerous times. In addition, the crew was accompanied by Lieutenant Colonel Clifford J. Agenbroad, operations officer of the 92nd Air Refueling Squadron, who had been at Fairchild for more than six years. Argenbroad was also an instructor-pilot who often went on flights to certify crew proficiency and was thought to be riding in the instructor’s seat directly behind Captain Cammack, and his copilot, Captain Herbert O. Zoeller.
Some aviation experts surmised that icing conditions could have caused the accident. But the pilot hadn’t reported any problems and there had been no emergency distress signal. Others speculated the radar altimeter, which should alert the pilot when the aircraft falls below a “minimum descent altitude” could have been rendered useless by the snowstorm. Recent studies had shown clearly that low-flying pilots, relying on radar altimeters in poor visibility over snow or thick ice, could be fatally misled by gross errors in altitude data.
On Monday, January 23, 1967, the Air Force sent a special team into the area to begin the arduous task of removing designated pieces of the wreckage to a hanger at Fairchild for examination. Their efforts, however, continued to be hampered by bad weather and heavy snowfall. A civilian construction company was contacted to cut an access road into the remote area from the Mount Spokane Ski Lodge. A large crane was brought in and lifted the heavy engines and larger pieces of the aircraft onto special sleds which were then towed away. Removal of the wing sections and smaller pieces of wreckage would be postponed until after the spring thaw.
On Friday, February 3, 1967, the Air Force announced that the investigation into the crash of KC-135, No. 56-3613, had been concluded. Colonel Culbertson, Accident Investigation Board chairman, stated that the cause would not be made public and declined to comment on whether the accident resulted from human error, flawed procedures, or mechanical failure.
Although the accident nearly duplicated the earlier KC-135 crash, Culbertson said that there was no similarity. That accident had been caused by navigational error combined with adverse weather conditions, whereas the cause of this accident was secret. Culbertson added that although the landing approach pattern to Fairchild AFB over Mount Spokane State Park would not be altered, board-recommended changes in the “particular instrument procedure” had been put into effect to prevent further such accidents.
Lieutenant Colonel Clifford J. Agenbroad, age 44, instructor pilot, Nampa, Idaho
Captain Billy E. Cammack, age 33, aircraft commander, Matador, Texas
Airman First Class Terry O. Fletcher, aircraft mechanic, Pasco, Washington
Captain Valentin F. Hemm, age 35, aviation psychologist, Mount Dora, Florida
Airman Third Class Michael R. Kerr, age 20, aircraft mechanic
Master Sergeant Orville Montomery, age 38, refueling boom operator, Saginaw, Michigan
Staff Sergeant Ralph D. Ogle, age 33, maintenance crew chief, Watertown, Tennessee
Captain James O. Wakeland, age 27, navigator, Godley, Texas
Captain Herbert O. Zoeller, age 30, pilot, Watertown, Wisconsin