Air Marshal Anil Chopra (Retired)
The US Air Force just lost one of its large supersonic B-1B Lancer strategic bombers in an accident at Ellsworth Airbase, South Dakota, on January 4, 2024. It was a routine training mission, but the weather at the time of landing was rough, with dense, freezing fog.
The bomber crashed on the runway, resulting in an “explosion and active fire.” Fortunately, ejection seats saved the lives of all four crew members. A few did suffer injuries, including to the back, a common occurrence when ejecting.
The fleet has since been grounded. The world vividly remembers the MiG-21 ‘Bison’ ejection of Wing Commander Abhinanadan Varthaman on February 27, 2019, during the Indian and Pakistan Air Force dog-fight chase. He landed nearly 7 km across the Line of Control into Pakistan-occupied J&K.
The author of this article is reportedly the only Air Marshal in the World to have ejected from a fighter aircraft in that rank.
Ejection seats are common in smaller fighter aircraft, but those in the larger B-1B have seen some successful seat ejections and some failures leading to fatal and near-fatal accidents in the past.
The B-1 has a four-person crew comprising a pilot, a co-pilot, and two weapons officers. It is the largest plane with ejection seats. All four crew members sit in an Advanced Concept Ejection Seat, or ACES II seat, with an escape hatch above.
The B-1B also has a last-ditch escape hatch on the cockpit’s floor. Currently, there are nearly 6,000 ACES II seats in service fitted on most American fighters and a few bombers.
The seat built by Collins Aerospace RTX Corporation has saved nearly 703 lives since it was introduced in 1978. The ejection can be activated by any crewmember to eject the entire crew automatically in less than two seconds. Alternatively, each seat can be activated individually.
When a crewmember pulls the ejection handle, the hatches above the crew are blown clear, and then rockets in the seats fire. The firing is sequenced to avoid collision between members. An early version of the bomber dubbed the B-1A, was equipped with a crew escape module encompassing the entire cockpit area and “was roughly the size of a mini-van.”
As the crewmember comes out into the airflow, the seats determine which of three parachute opening modes to use based on aircraft speed and altitude. If closer to the ground, the parachute deploys immediately.
At higher speeds, a drogue parachute will stabilize the seat before opening the main parachute. At very high altitudes, only the drogue parachute is initially deployed, and the main parachute is only at a much lower height so that the crew gets enough oxygen to breathe.
Evolution Of Ejection Seats
The initial workable concepts of the parachute were sketched by Leonardo da Vinci in 1485. The modern parachute was invented in the late 18th century by Louis-Sébastien Lenormand in France, who made the first recorded public jump in 1783.
As heavier-than-air aviation began, there was a need to bail out of airplanes. In 1911, Grant Morton made the first parachute jump from an airplane, a Wright Model B, at Venice Beach, California.
The initial exit from the aircraft was by jumping clear (“bailout”) and using a parachute. In many cases, this was difficult because of some injury, difficulty of egress from a confined space, g forces, the airflow past the aircraft, and other factors.
In 1916, Everard Calthrop, an early inventor of parachutes, patented an ejector seat using compressed air. The layout of the ejection seat was first evolved by Romanian inventor Anastase Dragomir and was successfully tested in August 1929 at the Paris-Orly Airport. The design was perfected during World War II.
The first modern day ejection seats were developed independently during World War II by Heinkel and SAAB. Early models were powered by compressed air, and the first aircraft to be fitted with such a system was the Heinkel He-280 prototype jet-engined fighter in 1940.
He-280 test pilot Helmut Schenk became the first person to escape from a stricken aircraft with an ejection seat in January 1942 after his control surfaces became inoperative. The first operational military jet fighter to feature an ejection seat fired by an explosive cartridge was the Heinkel He 162A Spatz. After World War II, with aircraft speeds increasing, such systems became even more important.
UK’s Martin-Baker became the first major ejection seat company in the late 1940s. In 1958, the Convair F-102 Delta Dagger was the first aircraft to be fitted with a rocket-propelled seat.
It was now possible to eject at supersonic speeds and also at a much lower height. Six pilots have ejected at speeds exceeding 1,300 km/h. Following an accident on July 30, 1966, two Lockheed M-21 crew members successfully ejected at a high Mach number at an altitude of 80,000 ft.
They fell into the sea. One survived, and the other drowned. However, most ejections occur at fairly low speeds and altitudes when the pilot can see that there is no hope of regaining aircraft control before impact with the ground.
The Ejection Seat Anatomy
Ejection seats are placed into the cockpit and usually attached to rails via a set of rollers on the edges of the seat. During an ejection, these rails guide the seat out of the aircraft at a predetermined angle of ascent.
Like any seat, the ejection seat’s basic anatomy consists of the bucket, back, and headrest. Everything else is built around these main components. Pulling the ejection handle on a seat sets off an explosive cartridge in the catapult gun, launching the ejection seat into the air.
The seat moves up the rails, the rocket fires to propel the seat higher, and the parachute opens to allow for a safe landing. The plane’s canopy has to be jettisoned prior to the ejection seat being launched from the aircraft. The seat, parachute, and survival pack all move out of the aircraft. Once in the airstream, the individual is automatically separated from the seat by the pilot extractor parachute.
Typically, the entire sequence between pulling the handle to the parachute opening may take around 2.5 seconds. Seat maintenance and checking the life of the cartridges and rockets are very important activities entrusted to specially trained technicians.
The parachute is a very critical part of the entire process. The parachute is packed in such a manner that it opens up quickly without the rigging lines fouling. The person who has packed the parachute before putting it in the seat deserves special thanks for every successful ejection.
Pilot Experience & Safety
Nowadays, there is only a seat pan handle located between the pilot’s knees. One pulls it to initiate ejection. The “standard” ejection system operates in two stages.
First, the entire canopy or hatch above the aviator is opened, shattered, or jettisoned, and the seat and occupant are launched through the opening. Aircraft designed for low-level use sometimes have ejection seats that fire through the canopy, as waiting for the canopy to be ejected is too slow.
There are leg retractors to prevent injuries to flailing legs. The pilot typically experiences an acceleration of about 12–14g during ejection. Some Soviet-era gun-barrel-type seats went up to 20–22g.
A zero-zero ejection seat is designed to safely extract the occupant from a grounded stationary position, zero altitude, and zero airspeed. Small rockets are used to propel the seat upward to an adequate altitude, and a small explosive charge is used to open the parachute canopy quickly for a successful parachute descent.
The minimum ejection altitude for an American ACES II seat in inverted flight is about 140 feet above ground level, while for its Russian counterpart (K-36DM), it is 100 feet. With a K-36DM ejection seat, one can eject at airspeeds from 0 to 1,400 km/h and at altitudes of 0 to 25 km (82,000 ft).
Pilots have successfully ejected from underwater in a handful of instances after being forced to ditch in water. The first recorded case was in October 1954, when a Royal Navy pilot successfully ejected underwater using his Martin-Baker Mk.1 ejection seat after his Westland Wyvern had ditched. Pilots of the US and Indian navies have ejected underwater.
Martin-Baker Company runs a club called the “Ejection Tie Club” and gives survivors a unique tie and lapel pin. The number of recorded lives saved by Martin-Baker seats is over 7,716 aircrew worldwide.
The author was a 5776 member of “Tie-Club,” having successfully ejected from a Mirage-2000 on February 24, 2012, using a Mk 10 seat.
Ejection From Other Aerial Platforms
The Kamov Ka-50, which entered limited service with Russian forces in 1995, was the first production helicopter with an ejection seat. The main rotors are equipped with explosive bolts to jettison the blades moments before the seat is fired.
The only commercial jetliner ever fitted with ejection seats was the Soviet Tupolev Tu-144. However, the seats were present in the prototype and only available for the crew and not the passengers.
The Lunar landing vehicles used ejection seats. The Vostok, Gemini, and the Space Shuttle spacecraft had ejection seats.
Normally, the force during ejection is not outside normal human physiological limitations. Ejection injuries could mean seriously bruised shoulders on the harness straps and possibly broken collarbones.
The spine or neck injury could occur because of incorrect posture during ejection or weak back muscles. Ejecting from an aircraft moving at speeds greater than the speed of sound (1,207 km/h) can be dangerous.
The force of ejecting at those speeds can reach in excess of 20g, which can cause injury. Compression fractures of vertebrae are a recurrent side effect of ejection. A flayed arm could cause shoulder injury.
One could have lacerations or concussions during the ejection caused by collisions with the canopy or fuselage. One could get injuries during a parachute landing because of bad landing posture or an undulating surface.
Ejecting below the seat-specified minimum height could be fatal. The final parachute descends to the ground at a vertical velocity equivalent to a free-fall jump from 12 feet height. Aircrews are trained on how to cushion the landing.
Ejection Survival Rate
There was a significant difference between ejection survival rates below and above 500 ft. Low-level ejections have a significantly increased risk of a fatal outcome. The survival rate of ejections below 500 feet was nearly 51%.
The survival rate was close to 92% at above this height. Many aircrew have delayed the decision to eject, and that resulted in fatalities. The delays could be due to inherent fear of ejection or hope of recovering the aircraft from the unusual situation.
Sometimes, there is just a second between life and death. Most air forces have ejection training, including a VR-style simulation where you pretend to parachute to the ground, running through the post-ejection checklist as you go.
Next-Generation Ejection Seats
The most important features of the new seats are the advanced safety technology, including head and neck protection, arm and leg flail prevention, and a load-compensating catapult rocket that varies its thrust based on the occupant’s weight.
American Collins ACES 5 is currently the industry benchmark for aircrew safety. These rugged ejection seats are made to withstand 40G crash. The target is to reduce overall ejection-related major injuries to less than 5% and ejection-related spinal injuries to less than 1%.
Reduced maintenance and life-cycle costs and increased aircraft availability.
The last thing a fighter pilot wants to do is eject. The perceived curse of losing the aircraft is often coupled with the thought of serious physical injury.
But compared to the alternative, the choice is clear. Ejection injuries can be reduced. Physical fitness, correct posture during ejection, aircraft altitude, and speed all determine the level of injuries. Seats are becoming safer. Timely decision to eject is most crucial.
- Air Marshal Anil Chopra (Retired) is an Indian Air Force veteran fighter test pilot and is currently the Director-General of the Center for Air Power Studies in New Delhi. He has been decorated with gallantry and distinguished service medals while serving in the IAF for 40 years. He tweets @Chopsyturvey
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