Bank angle and "G" forces - how they impact the human body and can be fatal


17 Apr 2022

Flight 507, a Boeing 737-800 operated by Kenya Airways, crashed in the initial stage of its second leg on 5 May 2007, immediately after take-off, killing everyone on board.

Kenya Airways Flight 507 | Representative | Source

According to reports, the plane tended to bank right, which the captain countered by using his control wheel. In the series of events that would follow, it was ascertained that there was a miscommunication between the two pilots and that the co-pilot hadn't acknowledged a verbal command by the captain requesting to activate the auto-pilot.

 In the 55 seconds that followed, the aircraft was piloted by neither pilot nor the autopilot. This eventually led to the aircraft increasing its bank angle from 1 degree, at the time the captain let go of the control wheel, to 34 degrees, when the bank angle warning kicked in.

By the time the captain managed to engage the autopilot, the aircraft was banking from 50 degrees to nearly 115 degrees at 2,290 ft. By this time, the aircraft was in an unrecoverable position and crashed into a mangrove swamp less than two minutes after takeoff.

Bank angle awareness

Representative | Quora

Loss of Control accidents can occur in one of the following three typical ways in which an unusual roll attitude can develop with delayed flight crew awareness:

When the flight crew temporarily fail to scan flight instrument(s) under the assumption that the autopilot is engaged, while it may be not (as was the case above)When the aircraft is flown manually in poor visibility conditions and solely based on external visual references.When there is a malfunction of the Attitude Direct Indicator (ADI) or Artificial Horizon (AH)

Electronic Attitude Direct Indicator | KLM UK Engineering Online Training

In all cases though, loss of bank angle awareness should be confined to just one pilot- Pilot Monitoring (PM) while any discrepancies (if any) should be corrected by the Pilot Flying (PF).

Instances, where there has been a successful recovery, are scarce, although it is to be noted that such occurrences can happen even in a flight deck with three members.

In addition to the loss of control, excessive banking can have significant effects on the G forces that act on a human body, depending on the degree of banking.

How do G forces impact the human body?

Science defines centrifugal force as something measured in g forces, with 1 g being gravity's effect on a person or object at or near the Earth's surface. Therefore, a rating of 2G means the person or object is experiencing twice the effect of gravity.

Assuming you are sitting or standing on solid ground right now, you are in a 1 G environment. Earth's standard force of gravity (G) is pushing against you as it normally does.

When planes make rapid turns, especially in the order of 90 deg or more, it creates a radial acceleration that can generate more than 6 G's of force- or six times the force of gravity of earth. This can have serious implications for humans who are adapted to survive in a 1G environment.

High-speed close-up view of a man's distorted face in GForce experiment in a wind tunnel | Representative | Getty Images

In a 1 G environment, the heart generates enough blood pressure to deliver the blood above the heart and to the organs above the chest. But in a rapidly building G environment, the acceleration force is strong enough to force the blood down the legs, making it difficult or almost impossible to flow back to the heart for re-circulationDr. Swee Weng Fan, a former flight surgeon and current managing director of training at NASTAR (National Aerospace Training and Research Center)

The human body can typically withstand about 5 Gs. At about 8 or 9 G, a human typically experiences blackout or loss of consciousness.

G-LOC | Representative | Sky Combat Ace

30 degrees of banking angle is typically the limit on a commercial passenger. 45 degrees would be deemed as "uncomfortable" by most passengers as in this case the load factor increases by 50% - giving a sensation equal to 1.4-1.5 times the body weight.

Airbus Fly-by-Wire (FBW) in normal law, apparently, doesn't allow banking exceeding 67 degrees as such a level turn would yield 2.5G - maximum for any transport category aircraft.

Types of G forces

+Gx – Gravitational force exerted on a pilot’s body from chest to back during take-off or sudden acceleration, pushing a pilot back into their seats.-Gx – Force exerted from back to chest, pushing the pilot forward. This may occur during landings or forward impacts.Gy – A lateral gravitational force that is exerted on the pilot’s shoulders, such as during a lateral roll.+Gz – A gravitational force that is exerted on the vertical plane of the body, such as during recovery from a dive or the pull into an inside loop.-Gz – Force exerted vertically as pilots push into dives.

An upwards acceleration of about 5g is enough to overwhelm the ability of the heart to pump blood to the brain. This causes oxygen starvation and the person can experience what is called G-LOC, or G force-induced loss of consciousness.

As arterial pressure in the eyes falls, pilots may begin to experience tunnel vision, gun barrel vision, and finally grey or blackout vision. These have often been the cause of numerous military and civilian aviation disasters over the last century.

Apparently, human tolerances of negative Gs are even worse. The negative Gs, force more blood to the head, causing vessels to burst in the eye- a condition called "red out" and, eventually, the brain. An extended force as low as negative 3Gs can be deadly.

A G force injury | Representative | MediHelp

All military and acrobatic pilots, therefore, train in Anti-G Straining Manoeuvre (AGSM) - these include various breathing and muscle-tensing techniques to minimize downward blood flow and keep the brain as oxygenated as possible. Additionally, pilots must maintain strong physical fitness, wellness and nutrition to stay alert in high-G environments.

Anti-G suit | Representative |

That said, limiting alcohol consumption, resting properly before the flight, and hydrating adequately for several days before flying can also help pilots with confronting extreme G-forces.


COVER: Futurism

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A dozen airport and airlines maintenance staff reported working drunk in India

Radhika Bansal

11 Apr 2022

A dozen airport drivers, firefighters and even plane maintenance staff reported working drunk in India in the first two months of the year, a regulatory crackdown found, reigniting concerns about flight safety in an aviation market that’s previously had issues with inebriated pilots.

Under a program initiated by India’s Directorate General of Civil Aviation, ground employees with IndiGo -- the nation’s biggest airline -- SpiceJet Ltd., and even Indian Oil Corp. were found to have failed breath-analyzer tests in January and February, according to a person familiar with the matter.

A first breach leads to a suspension, and repeat offenders may see their permits to work in airports confiscated, the person said, asking not to be identified because the information isn’t public.

Ground employees with IndiGo, SpiceJet, and even Indian Oil Corp. were found to have failed breath-analyzer tests in January and February 2022.

India in December revised guidelines to expand the universe of airport workers who would be subjected to breath-analyzer checks. Maintenance staff and anyone who visits the cockpit for inspection, audit or training were included.

The list has since been expanded further to include drivers of baggage carts, loaders, push-back operators and air traffic controllers, the person said. Expanding the testing pool will bring Indian airport safety and operation standards closer to global benchmarks.

Even when blood alcohol levels are near zero, the effects of any alcohol consumption can last as long as 36 hours, according to guidelines released in 2021. A spokesman for India’s civil aviation ministry, which oversees the DGCA, didn’t have an immediate comment.

Even when blood alcohol levels are near zero, the effects of any alcohol consumption can last as long as 36 hours

ALSO READ - DGCA orders pre-flight alcohol tests for 50% of pilots and cabin crew daily

IndiGo said in a statement that January 2022 “witnessed the peak of Covid cases during the third wave.” “Being on certain medication can also lead to employees failing the breath-analyzer test,” according to the statement. “However, cases of ground staff failing this test are far and few between. We follow all laid down protocols to ensure the safety of our passengers and employees.”

Representatives for SpiceJet and Indian Oil didn’t immediately respond to requests for comment. In 2018, a senior pilot with former state carrier Air India Ltd. -- who was also a member of the airline’s board of directors and was in charge of its overall flight operations -- tested positive on a breath test just an hour before he was scheduled to fly to London from New Delhi.

India in December revised guidelines to expand the universe of airport workers who would be subjected to breath-analyzer checks.

Two years earlier, the DGCA ordered Jet Airways India Ltd. and Air India to file police complaints against pilots who were found drunk, deploying legal action for the first time in such cases. Other countries and airlines have faced issues with drunk pilots.

Japan Airlines Co. was forced to put off a bond sale in 2018 and its president took a 20% pay cut for a few months after a pilot showed up drunk just before he was to operate a London-to-Tokyo flight.

A year later, South Korea’s transport ministry suspended the license of a pilot at budget carrier Jin Air Co. for 90 days for failing an alcohol test before a flight and imposed a 210 million won (USD 172,200) penalty on the carrier.

(With Inputs from Bloomberg)

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Northeast is a 'high-priority region' for PM, with 18 airstrips/heliports being built - Jyotiraditya Scindia

Radhika Bansal

11 Apr 2022

Civil aviation minister Jyotiraditya Scindia on Friday, April 8 said the northeast is a "high-priority region" for Prime Minister Narendra Modi as he went on to list the various initiatives taken up by the government for its development.

“In the last two-three years, we've developed a new airport terminal at Agartala, a new terminal is coming up at Holongi, a runway at Tezu is being upgraded. Eighteen more airstrips/heliports are being developed in the region,” Scindia was quoted as saying by news agency ANI.

ALSO READ - “Passenger operations from Agartala to Dhaka and Chittagong soon” – Tripura CM

The Union minister also said that a plan worth nearly INR 2,000 crore is in the works to develop the airport infrastructure in the region. “UDAAN has been a successful scheme for the region. We have given priority to Krishi Udaan here,” he added.

On April 12, two Dornier aircraft will be taken into operation by Alliance Air

“On April 12, two Dornier aircraft will be taken into operation by Alliance Air – they will operate from Dibrugarh to Pasighat, Tezu and Ziro in phase 1. In phase 2, Mechka, Vijoynagar and Tutling will be covered,” he further said.

ALSO READ - Alliance Air receives the first made-in-India civilian aircraft – Dornier 228

Last month, Scindia said the government has set a target of creating 220 new airports by 2025. He announced in the Lok Sabha while responding to demands for grants from the civil aviation ministry for 2022-23.

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With this, the government has set a target of creating 220 new airports by 2025 - Scindia

Stating that steps will be taken to simplify the process of granting pilot licences using advanced technologies, the minister added that the government intends to create 33 new domestic cargo terminals, set up 15 new flight training schools for pilots, and create more jobs, and increase focus on the drone sector. "With this, the government has set a target of creating 220 new airports by 2025," he said.

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Scindia also hailed the high proportion of women pilots in the country: "In all other countries, only five per cent of the pilots are women. In India, over 15% of pilots are women. This is another example of women's empowerment. There have been a lot of changes in the aviation industry in the last 20-25 years."

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The PIA Boeing 777 makes an emergency landing due to a cracked windshield

Radhika Bansal

11 Apr 2022

Pakistan International Airlines' (PIA) Boeing 777-200ER had to be diverted to Karachi for a safe landing after it suffered a cracked windshield because of a bird strike.

The plane registered as AP-BGJ was on a flight numbered PK9759 taking travellers from Lahore in Pakistan to Jeddah in Saudi Arabia at the time of the occurrence of the incident. It is to be noted that this is not the first time this jet has suffered the problem of a cracked windshield.

The PIA Boeing 777 makes an emergency landing due to a cracked windshield (Image Courtesy - SimpleFlying)

Before the emergency landing in Karachi, the PIA aircraft was destined to land in Jeddah with 350 flyers onboard. At 08:03 local time, the plane took off and climbed to a cruising altitude of FL320. The trip to cruising altitude took about 20 minutes.

The crew decided to divert to Karachi after witnessing a shattered windshield during the aircraft's takeoff and rise.

The windscreen of the First Officer was fractured, according to the Aviation Herald. After descending to FL140 and flying for another 85 minutes or so, the plane arrived in Karachi at around 10:25 local time and landed safely on runway 25L.

The cracked windshield of the PIA's B777. (Image Courtesy - The Tribune Express)

The airline then disclosed that the crew was forced to divert due to a bird strike that damaged the windshield.

The Boeing 777-200ER registered AP-BGJ was delivered to PIA in 2004 and has been part of the airline for 18 years now. Earlier, back in 2012, it suffered a similar incident of bird strike while flying from Karachi to Lahore. Similarly, in 2016 it was a victim of a bird strike flying from Jeddah to Lahore.

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Qantas announces direct flights between Sydney-Bengaluru, finalises codeshare with IndiGo

Radhika Bansal

11 Apr 2022

Australian carrier Qantas on Friday, April 8 announced it will start flights on the Sydney-Bengaluru route from September 14 onwards and is finalising a codeshare partnership with Indian carrier IndiGo. In a codeshare partnership, each carrier on its distribution system can sell seats on other's flights.

Currently, IndiGo has codeshare partnerships with Turkish Airlines, Qatar Airways and American Airlines. The Sydney-Bengaluru flight will operate four times a week from September 14 onwards on an A330 aircraft, a joint statement by both the airlines stated.

"These are the first direct flights between Australia and southern India by any airline, cutting almost three hours off the current fastest trip between Bengaluru and Sydney," it noted.

Currently, Qantas operates flights to India on only one route -- between Melbourne and Delhi -- five times per week. "Travellers are also set to benefit from improved one-stop access to Sydney from more than 50 Indian cities, as part of a proposed codeshare agreement between Qantas and IndiGo," the statement noted.

Once finalised, customers will have more convenient access from not only the major Indian cities, but many popular regional cities such as Pune and Goa, it mentioned. The proposed codeshare agreement will enable seamless connections via Bengaluru, Delhi, or Singapore to Australia's largest capital cities, it noted.

Currently, IndiGo has codeshare partnerships with Turkish Airlines, Qatar Airways and American Airlines.

"As part of the proposed agreement, customers who join the Qantas Frequent Flyer program will be able to earn and redeem points on connecting IndiGo flights (QF code only) and IndiGo will recognise Qantas Frequent Flyer benefits for tiered members (Silver, Gold, Platinum and Platinum One) including priority check-in, additional baggage allowance and priority baggage," it said.

Qantas customers travelling on IndiGo will enjoy the same baggage allowance for the entire journey as well as complimentary food and drinks, it mentioned.

Qantas announces direct flights between Sydney-Bengaluru, finalises codeshare with IndiGo

"The partnership will extend to Jetstar customers who will be able to book connecting flights on IndiGo services through its Jetstar Connect platform on, currently intended to start from late April," it noted.

“We are pleased to announce our proposed codeshare partnership with Australia’s flag carrier, Qantas Airways under Australia-India Economic Cooperation and Trade Agreement. Once finalised, this new partnership will enable the Qantas customers to fly to more than 50 unique cities on IndiGo via Bengaluru, Delhi, and Singapore with the access of 41, 33, and 6 destinations per station respectively.” Ronojoy Dutta, CEO, IndiGo

Qantas Group CEO Alan Joyce said demand for direct flights between Australia and India had grown steadily since both countries reopened their borders.

Qantas continues to offer a Fly Flexible booking policy with unlimited flight date changes available on flights booked before 30 June for travel until 31 December 2022 (fare difference may apply).

“For the first time, southern India will have a direct connection to Australia, which will make travel between the two countries more convenient and much faster for customers. The signing of the Australia-India free trade agreement will also drive travel demand as trade and investment links expand between Australia and India’s population of more than one billion people."Alan Joyce, CEO, Qantas Group

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Jetstar is a wholly-owned subsidiary of Qantas. "IndiGo will introduce reciprocal benefits for its customers to connect on Qantas and Jetstar in the future. Sydney-Bengaluru flights go on sale today starting from INR 78,380 return," it mentioned.

After the coronavirus-induced suspension of two years, India resumed regular international flights on March 27 this year.

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IndiGo and Jetstar team up in a virtual interline agreement

Radhika Bansal

09 Apr 2022

The Jetstar Group and IndiGo on Friday, April 8 confirmed a new Low-Cost Carrier (LCC) interline partnership that will enable Jetstar customers to book connections and flights on IndiGo services through its Jetstar Connect platform.

Launching at the end of April, the virtual interline partnership between the two LCCs is made possible by a technology company and flight search engine, Dohop.

The integrated booking engine allows customers to select flights and purchase both bundled and unbundled ancillary products, with customers connecting between international flights provided with seamless passenger and baggage transfer.

“We are pleased to announce the partnership with Jetstar. This strategic agreement will enable both airlines to tap into the rising demand for international travel, especially during this summer holiday season. The partnership will enable customers to book interline flights between the two leading carriers and enjoy access to a wide variety of destinations across Asia Pacific. This partnership will help us expand our international connectivity to yet another continent through Jetstar’s network.” William Boulter, Chief Commercial Officer, IndiGo

Jetstar’s chief customer and commercial officer, Alan McIntyre, welcomed the partnership and said as the world reopens it was great to offer Jetstar customers in Asia and Australia opportunities to travel to exciting new destinations in India through its partnership with IndiGo.

"The ability to partner with other LCCs through Dohop has opened-up a new world of possibilities, helping customers enjoy more seamless connectivity throughout the region. This new partnership enables Jetstar to offer our customers more destinations, more frequency and better connectivity, by combining our expanding network with IndiGo’s, all at the click of a button, fulfilling our vision to make more travel affordable.Jetstar Connect on provides more options for customers to access Jetstar’s great value fares and an expanded number of low-cost connections. This partnership opens up new services to Jetstar customers to incredible destinations such as Bengaluru, Mumbai and New Delhi through Jetstar’s hub in Singapore."Alan McIntyre, Chief Customer and Commercial Officer, Jetstar

Jetstar and IndiGo are also strategic partners of Changi Airport Group. Recognizing their joint potential,  Lim Ching Kiat, Changi Airport Group’s Managing Director for Air Hub Development said India was a key market for Changi Airport.

“In 2019, Singapore attracted over 1.4 million visitors from India to Singapore and with the relaxation of border policies, India has ranked among the top three countries at Changi in recent months,” Kiat said.

Jetstar Airways is a low-cost carrier and a wholly-owned subsidiary of the Qantas Group.

Jetstar Airways is a low-cost carrier and a wholly-owned subsidiary of the Qantas Group. Jetstar Airways launched Australian operations in May 2004, New Zealand trans-Tasman operations in December 2005, and New Zealand domestic operations in June 2009.

The carrier also serves short and long-haul overseas destinations. The brand also operates in a Singapore JV (as Jetstar Asia) and a Japanese JV (Jetstar Japan).

The airline operates an extensive domestic network as well as regional and international services from its main base at Melbourne Airport, using a mixed fleet of the Airbus A320 family and the Boeing 787 Dreamliner.