Bad day at Blackbushe

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Image: Erik Brouwer

An idiom (not to be confused with ‘idiot’) can be a surprising source of street (and flight) wisdom.

Idioms are ‘distinctive expressions whose meanings are not determinable from the meanings of individual words’. Here’s a favourite: ‘the straw that broke the camel’s back’.

This saying refers to the cumulative effects of seemingly minor actions producing dramatic consequences. Think a camel, after being laden to capacity, taking on one more tiny straw and a sudden ‘crack’ from the spinal area. Since we’re more about camel safety than camel husbandry, think now about reading a safety investigation after said spinal incident and the investigator concludes:

Direct cause of spinal rupture—one tiny straw. Recommend full review of straw-loading procedures.

You’d probably shake your head and sack your safety manager. And yet …

Consider the following ‘tiny-straw’ event in the early afternoon of 31 July 2015. The 57-year-old pilot of the Embraer EMB-505 Phenom 300 was in a rush and, to add to his troubles, the circuit area at Blackbushe was busy—really busy. It was a stark contrast to the last two weeks when he’d been enjoying some leisurely leave. It was also a stark contrast to the previous leg from Milan which had been completely routine. If only it could have stayed that way.

With the circuit at Blackbushe in sight, the pilot made his call to Farnborough. On board his corporate jet were three passengers keen to get on the ground and get on with their day in the UK. Farnborough Approach instructed the pilot to descend at his own discretion and, at four miles, to contact the local flight information service. The weather was clear with light and variable winds and, on any other day, would have been lovely weather for a safe and uneventful landing.

‘Turning base now and we should be taking downwind in less than one minute.’

The pilot of the Phenom 300 reported, prematurely and incorrectly, he was turning base. He was, in fact, turning cross wind—and doing so very fast. At 173 knots and with no flaps extended he was setting himself up—successfully—for a rushed traffic pattern. As he briskly proceeded through the before-landing checks, the aerodrome flight information service officer (AFISO) radioed to say there was an Ikarus C42 microlight aircraft ahead on downwind.

‘Roger that, we’ll maintain two thousand feet all the way,’ he radioed back.

Realising he was swiftly closing on the Ikarus the pilot initiated a climb to pass ahead of, and above, the microlight. Had he had the time to consider the significance of the name he might have thought it was probably a bad omen to climb above an aircraft called ‘Ikarus’. The traffic collision avoidance system (TCAS) emitted an urgent resolution advisory: ‘Descend! Descend!’ followed by ‘Maintain vertical speed’ and then ‘Adjust vertical speed.’

The TCAS was trying to warn the pilot of both the Ikarus and a different light aircraft that had entered the fray.

The AFISO, evidently concerned about the closure rate between the Phenom 300 and the Ikarus, radioed the microlight: ‘I’m not sure how this is going to work …’

‘We’ll extend on downwind to let the jet in first … if you’re happy with that,’ replied the microlight pilot.

‘That might work.’

The pilot of the Phenom 300, still in the climb and hearing the dialogue on the radio interjected, ‘I copy that. I was doing the same for him but in this case I’ll just … er … descend and do my landing.’

His radio transmission was halting and clipped. He was clearly struggling to assimilate the barrage of aural cues he was encountering from the AFISO, the other aircraft, the TCAS and Farnborough. In three minutes of manoeuvring, and apart from his own transmissions, the pilot was subjected to 19 transmissions on the Blackbushe frequency, 16 transmissions on the Farnborough frequency, 7 TCAS alerts and 8 automated announcements—basically every three seconds an announcement or transmission would sound overlapping and combining with the previous transmissions. The camel’s back was loaded and its spine groaning under the weight.

As the Phenom 300 rolled onto base it was still at 164 knots and its rate of descent pegged out at 3000 feet per minute. This added a new suite of sounds into the mix: terrain approach warnings (TAWS). At 3000 feet per minute and 164 knots the TAWS had every reason to complain. The aircraft was descending way too fast and an immediate corrective response was needed to avoid disaster. No response came. The aircraft continued its base turn with the TAWS pestering the pilot the whole way:

‘Whoop, whoop pull up!’
‘Whoop, whoop pull up!’
‘Five hundred.’

The ‘five hundred’ call occurred at 500 feet above ground level. For most operators this was considered to be the stabilised approach height—a designated height by which final approach speed and rate of descent were to be well and truly under control or else a go-around initiated. At 156 knots (50 knots beyond normal) and 2500 feet per minute, the Phenom 300’s approach was anything but controlled and yet the pilot persisted with the ugliness of the approach.

‘Whoop, whoop pull up!’

That was the final TAWS alert and the final straw as the Phenom 300 crossed the threshold at 50 foot, 154 knots and 1000 foot per minute. Incredibly, the pilot continued landing 700 metres along the 1000 metre runway. The landing was so wild the watching AFISO hit the crash alarm straight away. In his own, rather understated words, ‘It was clear at this time the aircraft was not going to stop.’

His prognosis was accurate. The Phenom 300 chewed up the measly 300 metres of runway and careened up an embankment that acted as an unexpected launch-ramp. With the wings still aerodynamic in 80 knots of airspeed, the jet briefly returned to the air for its last and violent flight. Within seconds it came crashing back down into an airport car park. The ugly approach got uglier as the jet collided with parked cars ripping off a wing and spewing volatile jet fuel in great gushes across its own fuselage and the cars with which it had just collided. A fire started quickly erupting into an angry conflagration. The firefighters sped towards the burning aircraft but were stopped because of a locked gate to which only the following truck and crew had a key. Inside the burning jet, the occupants desperately tried to open the door and evacuate. But the door wouldn’t open. The horrendous heat of the fire showed no mercy and within seconds all were dead with the firefighters reaching the aircraft too late to do anything to help the trapped survivors.

Lessons: Clutching at straws

When we read of an accident like this it’s probably in our nature to judge. Why didn’t he just shove the throttles forward and go around? Why didn’t he just do another circuit and get the aircraft under control? Why did he think he could get away with a touch-down at 150 knots with only 300 metres of runway remaining?

We can certainly judge but if we do judge we should be alert to the fact these kinds of judgments are ‘tiny-straw’ judgments—they assume the last straw is the only straw. Granted, the accident wouldn’t have happened if the pilot had gone around but to assert such workload-induced misjudgements as the only cause is to assert a tiny straw can rupture the spine of the camel. To rightly see an accident like this means we look beyond the last-straw landing to the great mass of accumulated organisational factors. That’s where we really see what broke the back of the Phenom 300.

So, what did break its back? We get a clue from the operator’s actions in the accident’s tragic aftermath. Firstly, and amongst other things, the operator insisted all Phenom 300 flights would be operated with both a commander and co-pilot unless the flight could be justified as a low work-load flight. Secondly, they introduced an enhanced recency program including improved stabilised approach training. And finally, they adopted a flight operations quality assurance program.

Of course, this means that for the accident pilot, there was no burden-lightening assistance from another pilot. Nor was there the benefits of improved proficiency and self-awareness from an ‘enhanced’ training system. And there was definitely no alerts or cautions from a healthy reporting system that might have, in the first instance, warned the pilot of the consequences of fast approaches and; in the second instance, warned management the pilot had a propensity for such approaches. In the 246 hours of recorded flight data, the aircraft’s combined cockpit voice and flight data recorder (CVFDR) faithfully recorded 20 previous flights from the accident pilot. On two separate occasions the CVFDR recorded threshold speeds of 150 knots with ‘pull up’ alerts and high rates of descent. The operator stated it had no knowledge of these previous events.

All these post-accident organisational initiatives point to pre-accident organisational failures in alleviating a burden that had accumulated to breaking-point. Again, it must be granted, the pilot’s decision to continue and the violent consequences were perhaps as shocking as a straw that suddenly breaks a camel’s back. But to think this was the only reason for the accident is to be like our fictitious (and soon to be sacked) safety manager who concluded the causal factor in the camel incident was one tiny straw.

And all this brings home an important lesson: If your operation is one which is constantly in a rush, one which constantly ignores safety lessons, or one which thinks an accident is a result of the ‘bad’ pilot in the Phenom 300, you would do well to carefully consider your next ‘tiny’ event.

It could be the last straw.

1 COMMENT

  1. The point is that Blackbushe is mainly a VFR field full of low and slow traffic and without an ILS or LPV approach and it is literally right next door to the full service business jet airfield of Farnborough….why choose Blackbushe over Farnborough? To save on the phenomenal landing fees at the latter? Or to minimize the likelihood of UK Border Force random checks? Who knows?

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