A sudden, strong and uncommanded pitch up immediately after take-off could have destroyed this airliner. Airmanship, teamwork and expertise stopped that from happening.
By Robert Wilson
Delta Airlines Flight 1080
Lockheed L1011 Tristar
San Diego – Los Angeles
12/13 April 1977
For Steve Heidt, becoming a flight engineer on the Lockheed L1011 Tristar was technically interesting but a sideways step in career terms.
Heidt, 30, had been flying since he was 15 and joined Delta Airlines as a Douglas DC-9 pilot after an enjoyable US Air Force career as an instructor on the T-38 jet trainer. But, after getting a crew posting to Atlanta in his home state of Georgia, he saw the prudence in putting his hand up to add a qualification on the three-engine wide-body.
‘I didn’t really want to be an engineer, I preferred to fly—it’s better to have something to grab on to,’ he says from near Atlanta, where he still lives. ‘But Delta said, “We’ve got too many DC-9 guys [pilots],” so I went through training on the L1011, then I went back to [flying the] DC-9.’
In April 1977 the phone rang at last. His first flight as engineer on the Lockheed L1011 would be a round trip from Atlanta via Dallas, San Diego and Los Angeles. At the airport he met the other crew members for the first time. Will Radford was first officer. ‘He was a really nice guy and a good pilot as well and we discovered we lived only about 40 miles apart.’
The captain, Jack McMahan, was the oldest, a World War II veteran who had flown the redoubtable Grumman Wildcat in the US Marine Corps. Despite this, he was no solitary hero, but collegial on the flight deck. ‘Jack was very pleasant, we talked about what he expected and he asked me what I’d been doing,’ Heidt says. ‘I said it was my first flight on the L1011 and he said, “Don’t worry. If there’s anything that happens too fast or you don’t understand just say. Will knows a lot about that panel and we’ll help you out”.’
Heidt enjoyed the first two legs of his first Tristar trip. The workload of a new type was balanced by the pleasure of working in a friendly but meticulous crew. He noted with approval how McMahan would apply subtle back pressure as speed rose on take-off to smooth the ride from the nosewheel.
At 11.53 on Tuesday night they lined up for the next-to-last leg, a short run from San Diego in far southern California, north to Los Angeles. The aircraft carried 52 people and a light fuel load.
Writing a year later in Airline Pilot magazine, McMahan described what happened just after take-off.
‘At an altitude of approximately 400 feet and airspeed of 168–170 knots, the pitch started to become excessive, exceeding 15–18 degrees. I was exerting a light push force on the control column and trimming electrically by use of thumbwheel trim when the thumbwheel movement stopped. The pitch controls felt very sluggish and I immediately attempted to utilise the mechanical trim wheel that serves as a backup system and overrides the electric trim. There was no response by the mechanical trim and I found that the trim was already zeroed out with full nose down stabiliser trim as indicated on the stabilizer trim indices and zero stabiliser indicated on the SPI (stabiliser position indicator) instrument. I reset the electric trim switches with no effect, and the thumbwheel trim remained immovable.’
Heidt’s memories are similarly vivid. ‘I see Jack moving the yoke forward almost to the stop—that’s not a good thing to be seeing from the engineer’s seat. He’s telling Will to get on the controls with him … and not only are the yokes full forward, they are at 90 degrees right. There’s a huge rolling moment as well.’
As a pilot for half his life, Heidt well knew the signs of approaching stall. ‘We’re over the ocean at 3000 feet and slowing through 140 knots. I’m thinking: “I didn’t sign up for this”!’
Shock, superstition and a recent tragedy were clouding McMahan’s mind, even as he called for checklists. ‘I remember thinking of the triumvirate theory, accidents occur in series of threes,’ he wrote. ‘There was the Canary Islands accident involving KLM and Pan American two weeks prior, the Southern DC-9 at New Hope, Georgia, the week before, and – the sudden realisation that you are about to become number three!’ He also referred to ‘some thoughts of a very personal nature,’ about the death of his 16-year-old son several months earlier in a car crash. Then the mental fog lifted in what he modestly described as ‘a very unusual experience’.
‘I had a clear mental image of exactly what the aircraft was going to do. Stall, roll to the left, and descend vertically disappearing into the clouds – at night – over water. The sensation was as if I was outside the aircraft and observing this occur from some distance away.’
Heidt, between rechecking his panel and ransacking his experience for solutions, was coming to a similarly morbid conclusion. ‘I was not afraid—that’s the funniest thing,’ he says. ‘I wasn’t afraid that I was going to die … I was really mad that I was going to die.
‘I knew we would go in the ocean, kill all the people and [the investigation] would say: “They were a bad crew.” I’d sooner not have that on my name.’
McMahan also realised he was seeing his own obituary: ‘Pilot became disoriented while executing a night over water take-off and encountering instrument conditions. I have read this statement a number of times as the probable cause. And with that abrupt thought, I was suddenly jolted into reality,’ he wrote. ‘We may lose this aircraft, but it will not be because we are not hanging in there and it will not be because of pilot error!’
McMahan felt ‘an intense compassion’ for the passengers and was freed to consider the equation of thrust, pitch, drag and airspeed. He found an answer.
Heidt says, ‘Jack, in his infinite wisdom took the two [underwing] outboard engines and pulled them all the way back. ‘I’m thinking “What in the world is he doing?”, but the nose, instead of trending upwards, started to trend more neutral. Then he pushes the number two [tail-mounted] engine full up, which is just above the fuselage centre line [and imparts a slight downward moment]. Then he brought the other two engines up a bit. That worked enough for him to try to make some sort of plan.’
Airspeed rose through 150 knots and McMahan was able to retract a stage of flap. The climb eased and they were able to tell Coast Approach about their flight control problem. At about 9000 feet, the Tristar broke out of the overcast into moonlight.
‘The flight attendant on the front jumpseat, Jane Hooper, is knocking on the door,’ Heidt says. ‘I open it and she looks in my eyes. I tell her we have a problem and she shuts the door and gets everybody in that airplane ready (by moving the 41 passengers to the front of the cabin). They did a great job.’
Pulling the flaps right up precipitated another climb. Again McMahan retarded the outboard engines and the aircraft descended to 10,000 feet where it entered a precarious equilibrium, maintaining between 195 and 197 knots, with a 12–14 degree pitch up and thrust set at the equivalent of climb power—engine one throttled up to counter the left roll, engine two in the tail working hardest to keep the nose down and engine three throttled back.
The crew now had time to consider where to land. There were several choices, all of them flawed. They held a quick informal parliament where McMahan declared he wanted to fly to Los Angeles and explained why.
Heidt remembers McMahan saying, ‘I don’t think we’re going to be able to go anywhere except Los Angeles—we don’t have enough fuel’.
‘No way was I going back to San Diego,’ McMahan wrote later. ‘The weather was VFR on the eastern side of the mountains and my first choice was Palmdale Air Force Plant or Edwards Air Force Base. However, it was now well after midnight and I knew that both these facilities normally close down at 10pm, leaving their control towers empty during this time of night.’
Phoenix and Las Vegas were also available but getting to either would involve crossing the Sierra Nevada mountains, a fool’s errand in a marginally controllable aircraft.
Coastal Los Angeles had one other grim advantage that McMahan spelled out. As Heidt remembers, the captain said, ‘I do not want to bring this uncontrollable airplane back over the ground and have it fall on people in their houses. We will stay out over the water and if this airplane comes apart, we will be in the ocean.’
Landing calculations were irrelevant. Heidt remembers McMahan saying ‘Don’t worry about trying to figure landing weights or speeds, because I don’t have a clue. We’re going to find a speed where it’s flying and we’re going to land at that speed.’
The aircraft descended into cloud again at 9000 feet on the approach. The crew shared the workload with Heidt taking the role of briefing the cabin crew and passengers. ‘I talked to the flight attendant and said we were flying it to the best of our ability but it may not work out so well when we hit the ground, and for them to be ready for evacuation or whatever is appropriate,’ he says. His address to the passengers was, of necessity, more reassuring.
At 5000 feet they intercepted the ILS for runway 6R and McMahan felt ‘we more or less had it made’. Sink rate was a steady 800 feet per minute, but the nose remained high and he mused they might have a tail strike if they landed in that attitude.
The first-generation cockpit voice recorder (CVR) only recorded the final 30 minutes of the flight. Soon after it starts, Heidt can be heard telling McMahan and Radford, ‘You’ve got the stabiliser [indicator] showing full nose down … and you’re not getting it … I can’t believe it.’
At 2500 feet McMahan extended the gear, which bizarrely sent the aircraft into a third pitch up. ‘I thought we had lost it, for sure,’ Heidt says. However, they recovered by resetting engine thrust and, almost to their disbelief, reacquired the glideslope at a new speed of 170 knots. At 700 feet, they broke out of the overcast with the runway dead ahead. Heidt remembers, ‘Jack landed that airplane, he didn’t flare but it was like landing on a pillow.’ McMahan used reverse thrust from the outboard engines to slow the aircraft but left the number two (centre) engine at idle. ‘Enough pitch ups for one day,’ he wrote.
Radford called the speed rolling off. ‘130, 120, 110, 100, 90, 80, 70 knots, 60 knots—thank God.’
The tower called, ‘Well, Delta 1080, everything okay?’ and McMahan said, ‘Tell ‘em we’re all right—we’ll take it to the gate.’
As the passengers left, several expressed annoyance that the flight had taken longer than scheduled. McMahan declined a debriefing (and a bottle of champagne, Heidt remembers) and took over another Delta Tristar for the crew to continue the flight to Atlanta. ‘Yeah, we were talking all the way,’’ Heidt says.
‘They took us back on one of those raised-up machines to the back of the airplane where the crank assembly was for the elevators,’ Heidt says. ‘It had busted. One elevator was full upright and the other was paired with the stabiliser.’ The combination of a leak and repeated pressurisation cycles had allowed water to enter the elevator crank bearing, eventually seizing it.
Lockheed began calling all L1011 operators that very day and the US Federal Aviation Administration (FAA) had produced Airworthiness Directive Amendment 39-2898 by the end of the week. Lockheed improved the protection and sealing of the bearing and this was the subject of a service alert bulletin.
In August 1977, the FAA presented McMahan with its Distinguished Service Award. Radford and Heidt received FAA certificates of commendation. When news of the incident broke the following year, all three had the rich pleasure of receiving contrite letters from the passengers who had complained about missing their connections.
McMahan, Heidt and (presumably) Radford were wrong about only one thing—the flight data recorder and CVR would have recorded the jammed elevator and posthumously vindicated them. But for those 55 minutes, their courage, professional pride and cohesion as a team made them something special.