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What is a tail strike?
A tail strike (or tailstrike) happens when the tail of an aircraft hits an obstacle on the ground. Depending on the severity of the shock, it can be classified as a serious incident or accident and results in damages requiring extensive repairs or even the hull loss of the impacted aircraft.
In general, tail strikes happen during take-off, landing or go-around when the pilots rotate or flare too sharply.
It can also happen when the aircraft is loaded or unloaded: if too much weight is placed at the back, an imbalance can occur.
Even if a tail strike might sometimes seem like a minor incident, it can cause extensive damage to both sensors and the structural integrity of the fuselage. The consequences can be as dramatic as an in-flight depressurization or breakup.
The hazardous effects of a tail strike
Here are two prime examples as to why maximum precaution is mandatory when dealing with tail strikes:
Japan Air Lines Flight 123 was a scheduled flight between Tokyo Haneda and Osaka Itami airports, operated by a Boeing 747 SR, a short range, high-density, variant of the Boeing 747 specifically made for domestic flights. JA8119, the aircraft involved (built in 1974), suffered from a tail strike back in 1978, during touchdown, due to too much flare. The rear pressure bulkhead was cracked open. Even though it was carried out by a Boeing technician, the repair wasn’t done according to Boeing’s manual (as shown below), nullifying its effectiveness.
Two Slice plates were used instead of one, reducing the repair’s effectiveness by up to 70%.
This botched repair allowed the cracks to spread along the rivets holding the panels together. Eventually, on August 12, 1985, the bulkhead split open, creating an explosive decompression, damaging all 4 hydraulic lines and tearing off most of the vertical stabilizer.
A photo made by one of the passengers, after the explosive decompression. The loss of cabin pressure forced everyone to wear oxygen masks.
Despite the heroic efforts made by the skilled pilots who managed to fly for another whooping 32 min, the barely controllable aircraft crashed on the side of Mount Takamagahara, 100 km away from Tokyo.
Only 4 passengers out of the 524 occupants aboard survived, making this tragedy the deadliest single aircraft accident in history. The accident came as a shock wave for Japan Airlines. The airline quickly changed its philosophy and improved its safety standards.
The story of China Airlines Flight 611, in 2002, is quite similar to JAL 123’s. The aircraft, a Boeing 747-209B registered as B-18255 (built in 1979), inbound from Taiwan to Hong Kong, struck its tail back in 1980 while landing. On May 25th, 2002, the rear pressure bulkhead separated from the rest of the aircraft before a complete mid-air break up, killing all 264 occupants aboard. The inquiry quickly pointed out that, once again, the 22 years old repair wasn’t done in compliance with Boeing recommendations, allowing the cracks to spread around the fuselage.
Tail strikes as immediate cause of accidents
Even though a tail strike is usually an insidious event ending up in accidents decades after its occurrence, it can also be the immediate cause of a disaster.
On July 6th, 2013, a Boeing 777-200ER, flying as Asiana Airlines Flight 214 between Seoul Incheon and San Fransisco international airports, was on final approach at the destination airport. The captain, who was the pilot flying, had to make a visual approach, in full manual control since the targeted runway was undergoing repairs. The aircraft descended below its intended glidepath and lost too much speed. When the pilots realized their mistake and tried to go around, it was already too late. The aircraft stalled and the tail broke off after violently hitting the runway’s seawall and the aircraft did a spin in the air before smashing against the ground.
Among the 304 occupants, 4 of them died, mainly from the sustained injuries after the impact
What can we do to prevent them?
To avoid tail strikes, additional training can be taken, especially when switching to a bigger variant of the same aircraft family, like when switching from an Airbus A319 to an A321 or from a Boeing 737-700 to a -900.
We can also add protective wheels at the tail like on the Concorde or the Boeing 737 for example
The Airbus A320 and A321, being the longest of the family, are more prone to tail strikes than their smaller siblings. To avoid that, these two, alongside other Airbus models, are fitted with new flight control laws that feature a limit to the maximum allowed nose up inputs, a pitch limit indicator on the Primary Flight Display (PFD) as well as an aural “PITCH PITCH” warning, indicating an impending tail strike.
Some airlines have placed a red “A321 “TAILSTRIKE CAUTION” ” label in the cockpit of their aforenamed aircraft, reminding pilots that their plane is longer than usual.
It is important to bear in mind that those systems cannot fully prevent such an event. In the case the inevitable happens, aircraft like the A350 or the B787 are also fitted with tail contact sensors that, when damaged, will close a system circuit, which will then inform the pilots or the dispatched ground crew.
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