ST. GEORGE — Airplane crashes have been a part of life for United States military aircrews since they first took to battle during World War I.
From the Great War through the Cold War and on into the modern-day battlefields of Iraq and Afghanistan, American aircrews have lost their lives in combat or during training missions.
On America’s front line of its military deterrent capability has been the B-52 Stratofortress.
On April 11, 1983, little more than 20 miles northwest of St. George, a B-52G (registration 58-0161) – call sign LURE 75 – slammed into the 7,050-foot Square Top Mountain. The B-52 missed clearing the summit by approximately 250 feet.
The accident resulted in the loss of all six of 58-0161’s aircrew and one observer who was catching a lift part of the way to his next duty station in California.
At the time of the crash, there were no bombs onboard.
The Buff (big ugly fat fellow) – an eight-engine strategic bomber – has evolved over time since it first rolled off the assembly line in 1955. It’s now capable of flying in excess of 640 mph while carrying 70,000 pounds of conventional bombs.
In its heyday, the Stratofortress was designed for one mission: To carry thermonuclear multi-tipped warheads to Russia and the Soviet Union’s puppet states in Europe as a retaliatory deterrence to mutually assured destruction from an exchange with the U.S. of the most powerful weapon known to mankind.
The typical yield of each nuclear weapon had more than 250 times the destructive power of the bomb dropped on Hiroshima near the end of World War II. The destructive power of the new age of nuclear weapons was large enough to create a 100% kill zone within a radius of 8.5 miles of its detonation point.
Since 1956, there have been more than 95 accidents involving a B-52 with the loss of nearly 360 air crew.
In the 1980s, depending on the B-52 variant, The Buff was equipped to carry different configurations of five different types of nuclear weapons: the 1.4-megaton B-28 bomb, the 9-megaton B-53 bomb, the 1.2-megaton B-83 bomb, the variable yield B-61 bomb, along with two types of air-launched cruise missiles.
In 2010, the B-52 was no longer assigned to receive nuclear-dropped gravity bombs. In 2017, the Air Force stopped listing The Buff as nuclear gravity bomb capable while retaining its nuclear cruise missile launch ability.
One of its more potent weapons capabilities is the nuclear-tipped cruise missile AGM-86B. The B-52 can carry up to 20 of the subsonic, low-flying missiles, releasing them at their maximum range of 1,491 miles to avoid enemy airspace.
Although the Cold War and the nuclear arms race started in the 1950s, little more than three weeks before LURE 75’s crash, on March 23, 1983, President Ronald Reagan announced plans for his Strategic Defense Initiative (SDI) commonly referred to as the “Star Wars” program.
The program envisioned a space-based missile defense system intended to protect the United States from ground-based and submarine-launched intercontinental ballistic missiles.
Reagan, a vocal critic of the Mutually Assured Destruction (MAD) philosophy, which the president described as a “suicide pact,” called on American scientists and engineers to develop a defensive system that would render nuclear weapons obsolete.
This act heightened unease between the Soviet Union and the U.S.
At the time of the crash, the beginning of the end to the Cold War was two years away.
Relations between the United States and the Soviet Union had never been more tenuous with both sides bracing for an exchange of nuclear weapons and stepping up training to carry out this unthinkable contingency.
LURE 75’s mission and its airworthiness
As part of America’s ongoing sharpening to its military preparedness, The Buff would regularly join “Red and Green Flag” combat training maneuvers conducted at Nellis Air Force Base, outside Las Vegas, Nev., which would often take the B-52 over Southern Utah en route.
LURE and a companion B-52, LURE 76, were both scheduled to depart from Robins Air Force Base in Georgia at 8:45 a.m.
The mission was multifaceted including cell departure (referring to both planes collectively taking off), a join-up over Oklahoma City, formation flying, high-altitude contingency training, low-level navigation/terrain avoidance, simulated weapons delivery and threat avoidance.
During pre-flight operations, LURE 75’s number four engine would not start.
According to the U.S. Air Force Mishap Report, the engine starter was replaced prior to takeoff. LURE 76 left Robins AFB at 1:47 p.m., with LURE 75 departing at 2:24 p.m.
During join-up over Oklahoma City, LURE 75 reported problems with its ground-avoidance radar. The radar navigators of both B-52s discussed procedures and possible actions to correct the malfunction, but there was no indication from LURE 75 that the problem was corrected.
At least twice during the flight, an Airborne Warning and Control System (AWACS) airplane – a mobile, long-range radar surveillance and control platform – needed to reorient LURE 75 after takeoff when it had deviated from its course.
The final conclusion was that the terrain avoidance radar had become so degraded, it was unusable.
St. George resident Maj. Donald Richardson, a retired B-52H navigator with 1,300 hours in The Buff, described flying in a B-52 as a lot of fun, but “it was a beast.” When you flew low level, it was “bouncing all over the place.”
“If the plane was having issues with its terrain avoidance radar, they could have climbed to the minimum safe altitude (MSA). When you are flying a low-level route like LURE 75 was, each leg has a minimum safe altitude,” Richardson said. “This gives you 500 feet of clearance – during each leg of the route – clearing the point of the highest terrain or object.”
Independent of the radar, Richardson added, the navigator and the crew would have had low-level charts to rely on to ensure that their route was safe.
“The charts would have indicated each MSA for that leg of the flight,” he said. “They could have aborted low level and climbed to MSA if the radar was unreliable.”
The official report did not speculate on why the crew failed to abort its low-level run and climb to a safer altitude into the Nellis training area.
“They could have climbed to MSA, which they didn’t,” Richardson said. “If they were having radar issues, or they weren’t paying attention, then the outcome was inevitable.”
The Air Force investigation noted that the crew did not consider the navigation system issues serious and the mission continued on with LURE 75 taking the lead and into the low-level entry point of the training exercise.
“Not to make assumptions, but during my 23 years in the Air Force, human error has to do with 90-95% of all crashes,” Richardson said. “Human error is almost always the deciding factor. If they failed to figure a work-a-round to the radar issues or became complacent, any number of things would have contributed to the crash.”
The flight recreation from the Air Force identified several command and control centers from Denver to Los Angeles, Utah, and the AWACS that tracked the B-52’s position and altitude.
Beginning at 6 p.m. and 14 seconds at an altitude of 19,900 feet, the B-52 descended in altitude during the next hour and 12 minutes. The final eight minutes detailed what may have been going through the flight crew’s thoughts as Square Top Mountain began to quickly loom large in the cockpit window.
At 7:15 p.m. and 35 seconds, LURE 75 dropped to its lowest point, 3,100 feet, as it flew along an upward-sloping valley approaching the mountain.
Less than two minutes later, the plane began to climb to 4,500 feet, less than two minutes more and the plane’s altitude was reported at 5,800 feet. Ten seconds more and the B-52 managed to climb to 6,300 feet.
Eleven seconds later, the plane would crash into the south face of Square Top Mountain.
At the time of impact, LURE 75 was traveling nearly 370 mph.
The specifics of 58-0161
The Boeing B-52G-95 (58-0161) was assigned to the 19th Bomber Wing based at Robins AFB, Ga.
The bomber was built in 1958.
Including modifications made since its manufacture, the bomber’s worth was estimated at more than $15.2 million when it crashed.
The plane measures nearly 160-feet long with a wingspan of 185 feet, and its eight Pratt & Whitney TF33-P-3/103 turbofan engines were each capable of generating 1,700 pounds of thrust. The bomber could reach a maximum airspeed of 650 mph and was capable of cruising at an altitude of 50,000 feet.
During the Air Force debriefing after the crash, chronicled by Aviation Safety Network, following the course corrections from the AWACS, navigator 1st Lt. Matthew W. Cervenak – who was the back-up for the original navigator with more experience – misidentified Square Top Mountain for another peak close by.
At the time of the crash, Cervenak had just over 500 flying hours – or about one year to 18 months – in the B-52 in the navigator seat.
Although the pilot, Capt. Donald Hiebert, had four times as many flying hours as his navigator, it was not noted in the crash report if improper cockpit management was a factor in the crash. However, the report did cite aircrew error, primarily Cervenak’s actions, as the leading cause of the crash.
Although only a handful of cockpit instruments were recoverable, crash investigators concluded the airplane was nose up in attitude and slightly left wing down in an attempt to bank and clear the ridgeline of Square Top.
“It appeared they were possibly in a steep climb and just didn’t have enough before they belly-flopped into the side of the mountain,” Richardson said.
At the time of the crash, the engines were running hot and fast. All engine bearings, gears and drive-shafts examined were receiving adequate lubrication at the time of the impact.
There was no evidence of a bird strike or other foreign object damage to the engines prior to impact.
Engine maintenance records were reviewed and no history of repeat write-ups or chronic engine performance trends were found.
More than 20 aircraft including fighter jets, cargo planes, and helicopters searched a 2,000-square-mile area for two days before debris was spotted and it was two more days before rescue crews made it to the crash site.
A first-hand visit to the location confirms the remarks made by an Air Force spokesperson at the time that the terrain was too rugged for a helicopter to land. The military opted to fly in a helicopter and hover over the crash site to lower a single rescuer by rope to see if any of the flight crew survived.
Despite a light blanket of snow that covered Square Top Mountain at the time, the wreckage was still smoldering when it was spotted.
“It looks like someone put a cigarette out on the side of the mountain,” said news photographer, Scott Henry in a New York Times article on April 15, 1983. “There’s not a piece of wreckage larger than a garbage can.”
Modern-day explorers to the crash site agree.
St. George resident Roger Edington has made the five-hour-plus hike saying “It looks like you put an airplane in a blender and scattered on the mountain. If you didn’t know what you were looking at, you would never know it was a B-52.”
Of the cockpit instrumentation, only an airspeed dial face, roll gimbal, Mach indicator dial, two fuel quantity gauges, a hydraulic gauge and the faces from two other gauges were recovered.
The cockpit area appeared to crash investigators to have broken up almost immediately upon impact with forces sufficient enough to catapult debris – including several of the B-52 engines – over the summit and on to the other side of Square Top Mountain.
Although the official Air Force incident report and the official debriefing cited navigation errors on part of the crew – primarily the “new” navigator – along with flight control avionics issues as the primary causes of the crash, a deeper dive into the record reviles a string of unfortunate circumstances and challenges that may have contributed to the mishap.
Standard piloting practices of the time, crew training, poor weather conditions, faulty cockpit instrumentation and inattention to communications with Nellis Control Center all could have contributed to the bomber’s destruction.
Although LURE 75 dropped to its lowest point during its mission at 7:15 p.m. and 35 seconds, the crash report transcribed radio traffic of the last eight minutes of the flight.
At 7:01 p.m. and eight seconds, LURE 75 began its final communication with Nellis, which centered on flight restrictions entering into the training exercise air space.
- 7:04:39 p.m. (Nellis) “Do you have Green Flag Restriction (Alpha)?
- 7:04:50 (Nellis) LURE 75, did you copy?
- 7:04:55 (LURE 75) Copy, Green Flag Restriction A.
- 7:05:02 (Nellis) (Controller lists all range restrictions).
- 7:05:29 (LURE 75) Control, 75, please repeat.
- 7:05:36 (Nellis) 75, Roger, do you have the Green Flag Restrictions aboard?
- (No answer)
“You always have to repeat back to the tower what they are asking,” Richardson said.
“Was it a failure in communication, yes and no. A lot of the radios were line-of-sight – meaning during low-level training the communication could have been blocked by the terrain … and sometimes it’s hard to hear the radio … but as the trailing aircraft – at a slightly different altitude – LURE 76 could have heard the communication and backed LURE 75 up on the radio call. They would have made sure LURE 75 heard the question. I don’t know if they did this or not, but the result ultimately was 75 crashing.”
- 7:05:46 (Nellis) “LURE 75 … you’re cleared as scheduled.
- 7:08:24 (Nellis) You need to be talking to your tactical agency, sir … (too garbled) … tactical frequency (AWACS frequency).
- 7:08:30 (LURE 75) And 75 copies, and uh” ……… (end of the last transmission)
Approximately 12 minutes later, LURE 75 would crash.
“My guess is they were flying low, with line-of-site radio coverage but too low, possibly not able to receive transmissions from the AWACS. They were experiencing radar issues … so a lot of little things contributed to this crash,” Richardson said. “But, they should have aborted and climbed up out of the cloud cover.
“When you have an accident like this, somebody was not paying attention. There is little room for error when you are flying that low. As an aircrew, we always feel we can recover from a bad situation. But, if the plane is falling apart around you, then it’s too late,” he added.
Originally part of the 28th Bomb Squadron, 58-0161, had been deactivated in early 1983 as part of the phaseout of the B-52G from the SAC inventory. Consequently, 58-0161 was reassigned to the 19th Bomber Wing.
In a letter, dated Feb 24, 1983, from the chief of flight training for the 28BMS, Maj. William W. Harris wrote “Due to the deactivation of the 28BMS and the significant reduction in flying hours, contingency training on a recurring basis will receive very low priority.
“Therefore … the possibility that individuals who were in formal training to complete contingency upgrades will probably not be completed,” Harris noted.
As aircraft are deployed to their new duty stations … all training should be maximized to ensure that aircrew members retain currency in those events which are required to maintain the highest level of readiness.”
It is unclear if the entire aircrew were up-to-date with ongoing training objectives.
On the day of the accident, both LURE 75 and 76 received a weather update from Nellis at approximately 5:30 p.m., which indicated there would be broken clouds at 15,000 to 20,000 with a minimum ceiling of 4,800 feet, visibility of seven miles and light turbulence between the ground and 10,000 feet.
When LURE 75 began its low-level training at 5 p.m. and 30 seconds, and LURE three minutes later (20-mile spacing), LURE 76 reported variable weather conditions through the insertion route – over Southern Utah – that required repeated transition between terrain avoidance altitudes in visual flight rule conditions and instrument-assisted flight rule altitudes to clear cloud obscured mountain ridges and peaks.
The USAF mishap report indicated that poor visibility played a role in the crash.
While it is unclear what were the minute-to-minute weather conditions during the last five minutes of LURE 75, the National Centers for Environmental Information weather records indicate that at the low-level insertion point of the flight, it would have been challenging from unsettled weather – including low cloud cover, rain and scattered snow – reported throughout the region.
The nearest weather readings were from an observer at Cedar City Airport.
“The temperature dropped throughout the day from 46 degrees down to 30 the following midnight with humidity starting out low and increased throughout the day. Snow showers were reported at 1,900 feet – with flakes reported at 1,700 feet – between 5-7 p.m.,” said Stuart Hinson, a meteorologist with the National Centers for Environmental Information.
Although the old airport in St. George was not equipped with weather radar capabilities in 1983, residents interviewed said light rain was falling in town and an employee at the airport said visibility was clear below 2,000 feet with cloud cover over most of the mountains surrounding the crash site.
The official surface weather report corroborates St. George’s weather assessment.
Beginning at 1:47 p.m. and continuing on through 8:25 p.m., mountain tops throughout Southern Utah were listed as obscured by the National Oceanic and Aviation Administration (NOAA).
When the smoldering wreckage was found, Square Top Mountain was covered in a blanket of snow surrounding the crash site.
The bomber’s legacy
There is a gravestone near the summit of Square Top Mountain. It is unclear who placed the gravestone, but the loss of the crew has not been forgotten.
Last December, as part of the St. George Wreaths Across America remembrance, a wreath was placed on the headstone of the flight crew of 58-0161.
The National Wreaths Across America is a coordinated wreath-laying effort, held in December, usually accompanied by a patriotic ceremony, at Arlington National Cemetery as well as wreath-laying events at cemeteries in all 50 states, at sea and abroad, according to information from the Wreaths Across America website.
Valerie King, regent of the Daughters of the American Revolution Color Country Chapter in Southern Utah, helps organize the annual wreath-laying ceremonies at St. George, Tonaquint and Shivwits cemeteries. King said between the three cemeteries, approximately 2,100 wreaths were laid to honor veterans last year.
It is the mission of Wreaths Across America to remember the fallen U.S. veterans, honor those who serve and teach children the value of freedom. The organization’s mission is reflected in the wreath-laying ceremony in which each veteran’s name is said aloud as wreaths are placed upon their graves.
Perhaps one of the most poignant wreaths laid – placed by Roger Edington – is on Square Top Mountain and the crash of 58-0161, King said.
“I think the wreath is a wonderful way to honor and remember those who have served to preserve and protect our freedoms,” King said. “They are not forgotten as long as their names are said. A soldier dies twice. Once when they take their last breath and a second time when their name is no longer spoken.”
58-0161 crew lost
- Pilot – Capt. Donald Hiebert, 28, of Shirley, Mass.
- Copilot – 1st, Lt. Thomas C. Lennep Jr., 25, of Brownsville, Texas
- Navigator – 1st, Lt. Matthew W. Cervenak, 24, of Jacksonville, N.C.
- Electronic Weapons Officer – 1st, Lt. Bernard S. Russell, 26, Anniston, Ala.
- Radio Navigator – Capt. Jonathan M. Bishop, 27, of Fairhope, Ala.
- Air Gunner – Staff Sgt. Major Carter, 25, of Savannah, Ga.
- Pilot/Observer – Col. Caroll D. Gunther, 45, of Salina, Kan.
The ill-fated flight would have been Hiebert’s last piloting a B-52. He had been assigned to a new duty station at the Pentagon.
On the day of the crash, Hiebert’s wife Pam was planning to meet her husband on the runway after landing at Nellis with a bottle of champagne. The celebration of more than 2,000 hours in a B-52 never happened.
Hiebert was described as a devout Christian, concerned with the well-being of others and possessing the ability to leave a lasting impression on others.
Whether his time was spent with Boy Scouts, the youth group at his church, as president of the parish council or singing with the chapel music group, he wanted to be involved with people.
He took time to say “I care” to the budding athletes on a Little League team and to share the pains of growing up with searching teenagers on a church retreat. “Donny passionately believed that our hope for tomorrow lives in each of us today,” the memorial noted.
In a letter written two years prior to the crash, Hiebert would say, “I only want to raise a family, serve my fellow man (mostly young people), give credence to the Gospels, strive for holiness, and be a gentle soul. I’d rather teach philosophy than poli-sci, fly a kite than a B-52, lead my family in prayer than men into battle. And yet, this profession means so much to me.”
Richardson does not question Hiebert’s professionalism, but said because it was his last flight onboard a B-52, he might have “pushed the envelope on April 11, 1983. We will never know.”
Military Aviation Archaeology / Lost Flights, United Press International, Vegas Hikers, Aviation Safety Network, The New York Times, Washington County Historical Society and the Bureau of Aircraft Accidents Archives, Air Force Technology, the War Zone, the Federation of American Scientists, Popular Mechanics and the United States Air Force contributed to this article.
Attempts to contact the flight crew’s relatives were unsuccessful.
To access the source material provided click on the hyperlinks available within the article. Additional background information can be found at:
- FAS Nuclear Notebook: US nuclear forces, 2017 (publication researched and produced before the Obama administration announced a 500-warhead reduction of stockpile in early 2017. Updated numbers.
- Increasing Nuclear Bomber Operations.
- LRSO: The Nuclear Cruise Missile Mission.
- Forget LRSO: JASSM Can Do The Job.
- W80-1 Warhead Selected For New Nuclear Cruise Missile.
Copyright St. George News, SaintGeorgeUtah.com LLC, 2021, all rights reserved.