Air Safety

Recent RAAF experience has shown poor ATM to be a contributor to aircraft accidents. Problems can arise with the captain who is too aggressive, working and making decisions in isolation and ignoring all the expert advice available. The submissive captain can. also produce problems, allowing his judgement to be clouded by the input of other crew members. Other crew members are also involved; the copilot who contributes nothing before or during an accident sequence is equally not performing his duties.

ATM is applicable in any crewed aircraft, although it is in the airline industry that it has come to the fore. More and more, however, the military is quoting a breakdown in ATM as being causal in flying accidents. To illustrate good and bad ATM and the value of training, a comparison is made between two recent Boeing 747 incidents and between a Boeing 727 and a Lockheed Electra incident. ATM techniques and the lack of them, are ably illustrated in the following two near disasters.

Boeing 747 Flame Out

On the night of 24 June 1982, a British Airways Boeing 747 flew unwittingly into a volcanic ash cloud from the erupting Mount Galunggong volcano. At the beginning of the incident the captain was off the flight deck, but was recalled when smoke was seen coming from the floor vents and the windscreen was lit up with what appeared to be an intense display of St Elmo’s fire. The weather radar showed nothing. The engines were also glowing as if lit from within and the electrical discharges created a stroboscopic effect so that the fans appeared to be slowly rotating backwards.

The captain decided to concentrate initial efforts on the air conditioning smoke but, before he could react, the No4 engine failed, The routine engine fire drill was duly performed. Soon after No2 failed, followed by No3, then No1. The crew throughout the sequence were concerned that somehow they had done something wrong but, nevertheless, continued to perform their functions. The captain assessed the aircraft state. He believed that all generators should have been lost, yet instrumentation, lighting and the autopilot were still working. The engine instrument display was confusing as some instruments were designed to drop off scale and some to freeze under no power conditions. However, he continued to fly the aircraft, noting a decrease in airspeed and setting up the autopilot for a descent. He instructed the copilot to declare an emergency (radio contact was difficult to impossible whilst in the volcanic cloud).

The copilot and flight engineer worked together completing the shutdown checks, consulting the checklists and attempting the relights. The captain meanwhile monitored the aircraft, allowing the autopilot to fly it, while he thought through possible alternative actions. The passengers were alerted and information passed to the cabin crew.

During the descent the oxygen masks automatically deployed as cabin pressure decreased. The copilot’s mask was unserviceable, so the captain decided on an emergency descent, but modified it, not lowering the gear. The copilot’s mask was repaired and the best descent profile for maximum range was regained. A discrepancy of 50 knots was then noticed in the airspeed indicators and the air speed was adjusted as it was feared the higher speed may have been too high for a successful engine relight.

Following the multiple engine failures, the aircraft had been turned north towards Jakarta. However, between the aircraft’s position and Jakarta was a mountain range with a safety height of 10,500 feet. The crew decided to track towards Jakarta but, if the mountain range was not crossed before 12,000 feet, a turn back would be initiated and a night ditching performed in the sea.

Relight attempts were made continuously on all four engines. These attempts resulted in ignition of the fuel behind the engines which appeared to passengers and crew in the rear of the cabin as if the engines were on fire. Although these people were very alarmed, the cabin crew, who knew little more than the passengers, performed a remarkably professional job in calming both the passengers and themselves.

About 12 minutes after the initial flameout, No4 suddenly relit. Within two minutes the other three engines also restarted. The aircraft was then at 12,000 feet.

Continuing on towards Jakarta, a climb was initiated but, at 15,000 feet, the St Elmo’s fire resumed. The aircraft was levelled and No2 engine shut down due to continuous surging. It was decided to descend below the St Elmo’s fire height, but to use aerodynamic speed control and not to touch the throttles unless essential.

On approach it was discovered that visibility was severely reduced except through the copilot’s side window and the captain’s windscreen through a small section at the edge. Crew co-operation was good with the captain flying a localiser until able to pick up the VASI and the copilot and engineer calling out the other parameters, such as distance and height.

Damage to the aircraft was extensive. The leading edges, windscreen, flying surfaces, engine nacelles and nose cone – all appeared as if sand blasted. The engines were badly affected with the turbine blade tips literally ground away.

It was not until the following day that the crew discovered they had flown through a volcanic cloud. Although not understanding the problem and believing themselves to be in the wrong, the crew maintained its cohesion by employing good ATM techniques. The resulting persistence prevented a likely catastrophe.

Boeing 747 Loss of Control

The second Boeing 747 incident (involving a China Airlines 747SP) occurred while the aircraft was cruising at 41,000 feet when No4 engine lost power. The captain allowed the autopilot to continue flying the aircraft but became alarmed at the decreasing airspeed. After three and a half minutes he disconnected the autopilot to manually fly the aircraft in an attempt to regain airspeed. In concentrating only on airspeed he missed other cues such as the amount of aileron deflection the autopilot had introduced. Consequently, upon disconnecting the autopilot the aircraft pitched down and rolled right, completing a 360° roll and diving to 9,500 feet in under two minutes.

Two passengers were seriously injured and the aircraft sustained major damage. Both wings took on a permanent set, 1o feet of the left horizontal stabiliser and the entire outboard elevator separated, sections of the right stabiliser and outboard elevator separated and many cracks and broken mounts resulted.

The NTSB determined that the probable cause was the captain’s preoccupation with an inflight malfunction and consequent failure to properly monitor the aircraft’s flight instruments, resulting in loss of control. A contributing cause was the captain’s over reliance on the autopilot following the loss of thrust.

The captain gave little instruction to his crew, apart from asking the copilot to obtain a clearance to descend. The copilot did this, summoned the flight engineer forward and also monitored the aircraft, warning the captain of the decreasing air speed and increasing bank. The copilot, without being asked, came onto the controls with the captain.

Training and ATM

The following examples illustrate the value of ATM training. The first crew were trained in ATM techniques, the second were not.

Comparing the Two

Unlike the British Airways incident, which could have been disastrous but for good crew coordination, this more recent incident was compounded into a near disaster by the inaction of the captain. In the first incident the captain ensured someone flew the aircraft; in the second, the captain overlooked this essential by concentrating solely on airspeed. In the first the captain ensured good management of the emergency by directing the use of checklists, by encouraging inputs from the other crew members, by innovative thinking and by pure persistence. The captain’s input in the second incident was not positive; the copilot was left to do most things on his own initiative. One captain displayed good ATM technique; the other did not.

Boeing 727 Windshear

The ATM trained crew were operating a Boeing 727. During the takeoff a hesitation in airspeed increase was the first indication of the problem to follow. As the aircraft rotated at the VR of 141 knots, the copilot called decreasing airspeed and the second officer followed with “You’ve lost 20 knots”. The captain stopped the rotation and held about 8° nose up while calling for maximum power. The first officer ensured the throttles were full forward. Airspeed fell to 130 knots, but the captain maintained and selected climb angle while the second officer informed the captain of rate of climb (zero for some time) and the effect of aircraft attitude on performance. Once VR was regained the captain selected a normal climb attitude while the second officer continued to supply the captain with other useful information. At about 700 feet the aircraft cleared the windshear and continued to climb. When the aircraft would not pressurise, the decision was made to return. It was then discovered that a localiser antenna, positioned 1,000 feet from the departure end of the runway, had been struck. The NTSB report praised the coordination and communication of the crew. Apart from flying technique and positive action, the crew responded well as an entity to avoid disaster.

Electra Vibrations

In contrast to this Boeing 727 incident was a Lockheed Electra crash which took 70 lives. In this accident the crew were not trained in ATM techniques.

It was a fairly long day with a number of stops and the flight was behind time. The cockpit voice recorder (CVR) later revealed missed checks, checks done in the wrong order and checks to which no response was recorded. Unknown to the crew, the aircraft taxied probably with the air start access door on the right wing leading edge unsecured. During the takeoff the CVR recorded two distinct thumps. After he called for gear up the captain asked the flight engineer “What is it?” and the flight engineer responded “I don’t know”. The flight engineer called METO power set and soon after, the captain told him to reduce power. The captain then directed the copilot to get permission to return and to tell the tower of a heavy vibration. The copilot became engrossed in conversation with the tower over fuel and POB; at one stage both pilots talked on the radio.

Four seconds after the ground proximity warning system (GPWS) sounded, the copilot called “100 knots” and repeated his call three seconds later. After a further three seconds the captain called for full power and six seconds later the aircraft crashed, only 16 seconds after GPWS sounding and only 47 seconds after the captain directed the copilot to get permission to return.

The NTSB found that the aircraft should have been controllable and that in past instances vibration severity had been reduced by reducing the angle of attack. The captain attempted to determine the cause of the vibration and fly the aircraft simultaneously. Unlike the Boeing 727 incident, the Electra captain tried to do everyone’s job and did not heed the copilot’s airspeed calls soon enough to recover. The copilot allowed himself to be distracted by radio communications rather than monitor the aircraft.

The Value of Training

If the Electra crew had been given an ATM course they may well have similarly reacted to their emergency to the Boeing 727 crew. ATM would have taught them that in an emergency someone must fly the aircraft, while the others troubleshoot and there must be no doubt who is doing what. When flying the aircraft becomes the primary consideration (as it did at VR for the Boeing 727 and should have been done when the GPWS activated in the Electra), all assistance should be given to the pilot at the controls who may not be the captain; communicate with him and tell him how the aircraft is responding. The <. aptain needs to make quick, positive decisions and therefore, also needs timely information fed to him by other crew members. If loss of control or collision is imminent all distractions such as radio calls and even troubleshooting must be at least be temporarily set aside until the aircraft is recovered.

Australian Airlines conduct an Aircrew Team Management (ATM) Course over three days (refer p. 96 Mar 86 AA). A number of RAAF pilots have completed this course and highly recommend it. The RAAF is currently negotiating to have a minimum of 48 personnel trained each year. The course covers team work, decision making, communicating, conversing, interpersonal skills, understanding people and cockpit management. Training techniques include team decision exercises, simulations of aircrew critical choices, group discussions, role playing, case studies and videos of flying incidents.