Can a plane still fly and land safely should it lose both its engines? This is a question that is frequently asked and needs to be answered to dispel doubts. Capt. Lim Khoy Hing explains what a Dead-Stick glide is and why, despite engine failures, it is possible for any trained pilots to safely land an aircraft on any fl at open ground.
A Dead-Stick landing is when all the engines of a plane are lost and the pilot is forced to land on any flat open ground ahead. This term was coined a long time ago and refers to the old wooden propellers (stick) of planes. The description, when used, is often misunderstood as the flight controls in most planes are either fully or partially functional even with no engine power. The plane is still controllable in such situations. This reminds me of when I won the Dead-Stick spot landing competition in a flying club (Royal Selangor Flying Club) many years back. In this competition, the pilots flew single engine planes and the object of the game was to touchdown nearest to the threshold (beginning) of the runway. If a pilot landed short of the threshold, it’d get him disqualified. Those were the good old days when flying was cheaper (petrol was less than USD30 per barrel) and pilots not only had loads of fun flying but were also able to sharpen their skills.
Landing In Dire Straits
The Dead-Stick landing comes in handy if one has to cope with a glide landing. This was precisely what happened to a Canadian pilot in 1983. He managed to glide-land a Boeing 767 safely on a disused runway when it ran out of fuel due to an error in the refuelling process. In my 45 years of flying, I’ve practised for and been tested many times on how to cope with either one- or two-engine failure (in a 4-engined plane). However, I have never had the misfortune of encountering any such incidents in real life. Thus, it comes as no surprise when safety experts say that the odds of an engine failure is one in 800,000 and two engine failure is even more remote – one in 8 million! In fact, you’d have a better chance of winning a state lottery.
Ensuring Continued Safety
The airline industry continues to promote engine failure training and takes no chances in their efforts to ensure the safety of air travellers. When I attended the pilot selection process before becoming one, one of the ways to check our flying potential was to test our psychomotor skills (mental and muscular ability) using an archaic mechanical bench. Fast forward to the present, the pilot selection is more advanced and stringent using the ADAPT system – a computerised pilot selection and assessment process that is also used in selecting F1 drivers, ensuring the newer pilots become even more adept in their skills.
Regardless of how remote the chances of the Dead-Stick emergency becoming a reality, pilots are still subjected to many, many rigorous check flights so that they’ll always be prepared for engine failures at all take-offs. It is something that has been ingrained into the pilots’ consciousness, so that they know instinctively what needs to be done should this event ever occur.
Handling A Dead-Stick Landing
Unlike a normal powered landing, a Dead-Stick landing requires skills and good judgement. An error in selecting the flaps or landing gears prior to touchdown is generally irrecoverable and the plane will land short of the runway. A plane with two failed engines would glide at almost twice the rate of descent of a powered aircraft. The trick is to stay high. For the technically minded readers, let me elaborate (unofficially). For instance, on a Boeing 737, the pilot should position the plane on the centre line of a runway at a minimum height of 6,000 feet when 15 nautical miles out. When assured of a safe touchdown, the pilot would lower the landing gears at around 1,000 to 500 feet and very close to the runway (a very crucial action).
However, on an Airbus plane, when both the engines are lost, only limited electrical powers are available with the aid of the RAT (Ram Air Turbine) – an emergency generator that automatically extends when it senses two engine failures. The RAT has a mini fan and is powered by airflow when the plane glides down for a landing. To lower the landing gears in this scenario, the system makes use of gravity. This is achieved by releasing a mechanical lock. To stop the plane, it has the emergency brake (accumulator) to supply about seven applications – enough to bring the plane to a complete stop.
Glide Landings In Real Life
There have been several instances of commercial planes successfully carrying out Dead-Stick landings. In July 1983, an Air Canada Boeing 767 ran out of fuel en-route from Montreal to Edmonton. However, the crew managed to make a successful Dead-Stick landing at an abandoned airfield at Gimli where a car rally was in progress. In August 2001, an Airbus A330 near the Azores Islands in the Atlantic Ocean lost both engines as a result of fuel starvation. The crew was able to glide the plane for 20 minutes (about 115 miles) to an airfield and averted a water landing. None of the 13 crew members or 293 passengers were seriously injured. In January 2009, an US Airways Airbus A320 made successful Dead-Stick water landing at the Hudson River, New York with no loss of lives amongst the 155 people on board.
The Challenge In Dead-Stick Landing
A dead-stick landing is often quite challenging. Recently, at the end of the training course for my two hardworking Japanese students, both requested that I set up a scenario in the flight simulator to enable them to practise the exercise. I am quite happy to report that they successfully landed the plane without any problems. It gave them tremendous confidence knowing they may do just as good as Captain Sully of the Hudson River water landing fame!
All airliners have the capability to glide when all the engines are lost. They do not drop down like a stone but would continue to glide horizontally while descending. The success rate of this very rare incident shows that not all is lost when a plane loses all the propulsive powers in flight. Lest the thought of engine failure worries you, let me reassure you that airplane engines are generally very reliable and flying is one of the safest forms of travel. It is safer than you going to the supermarket in your car. A US National Safety Council study showed flying to be many times safer than traveling by car and that more people die on the road in the US in a 6-month period than all the commercial air travel fatalities WORLDWIDE in 40 years!
Captain Lim Khoy Hing is a former AirAsia Airbus A320 and AirAsia X A330/A340 pilot who also used to fly the Boeing 777. He has logged a total of more than 25,500 flying hours and is now a Simulator Flight Instructor with Air Asia X. In his spare time, he shares his opinion on aviation issues with others. For more air travel and aviation stories,check out his website, ‘Just About Flying’ at www.askcaptainlim.com.