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On January 11, when IndiGo Airlines’ flight 6E 333 had a bumpy touchdown at Goa International Airport, it was a close brush with disaster for over 100 passengers aboard the A 320. The woman pilot in command landed the plane on its fragile nose wheel — an erroneous manoeuvre that could have even led to the flying machine disintegrating and catching fire.

Alarmingly, an inquiry conducted later by the Director General of Civil Aviation ( DGCA) revealed that on 15 to 20 earlier occasions, Captain Parminder Kaur Gulati landed the aircraft at an angle indicating that the nose wheel may have touched the tarmac first. This is unheard of in aviation circles. Aircraft normally land on the main landing gear ( MLG), comprising the two sets of rear wheels. After these bigger — and sturdier — wheels touch the runway, the speed of the plane is reduced. This is followed by the already opened nose landing gear ( NLG) — the smaller front wheel just below the cockpit of the aircraft — coming in contact with the surface.

Flight 6E 333 took off from Indira Gandhi International Airport in Delhi and was bound for Goa. Abhas Gupta was Gulati’s copilot aboard the aircraft. Captain Gulati appeared to have been so oblivious to the abnormal and highly risky touchdown at the Goa International Airport that she just reported the incident as a “rough landing”. Not only did the steep descent leave the passengers’ hearts in their mouths, it went against the recommendations of aircraft manufacturer Airbus, too. This was not the end of the matter.

After the rough landing in Goa, Gulati and the engineer concerned merely carried out an inspection of the aircraft and reported that everything was normal. The airbus was, therefore, cleared to fly back to Delhi. The Indigo flight 6E 332 — with passengers on board — started its return journey to Delhi. But midway through, the plane’s electronic systems signalled a problem in the landing gear. The warning related to the nose undercarriage being internally damaged.

The electronic signal that flashed in the cockpit showed that the landing gear didn’t retract because it was stuck in the “ down position”. The Indigo aircraft had to then return to Goa to offload the passengers. Later, it took off from Goa without the passengers and landed at IGI Airport. The combined probe carried out by the DGCA, Airbus and IndiGo confirmed that the aircraft had landed on the NLG first, followed by the MLG. “This is a non- conventional landing,” the report accessed by M AIL T ODAY said.

Gulati’s flying history came under the scanner of the investigators. An analysis of the digital flight data recorder ( DFDR) of the aircraft she previously flew pointed out that in her 15- 20 earlier landings the ‘ touchdown attitude’ was 3.8 degrees, which went against the recommended attitude of 5.8 degrees. Though within the safety zone, this increased the chances of the nose wheel touching first, the report stated.

The standard glide angle followed by an aircraft during descent is 3 degrees and the nose of the aircraft should be at 2.5 degrees at the horizon level. Just before touchdown, the latter is increased to 5 degrees. However, in the IndiGo flight’s case, the pilot gave a negative pitch attitude and reduced the angle to 3.8 degrees resulting in the aircraft landing on the NLG. The report disclosed that the auto pilot was disconnected at 311 feet above ground level. At 100 feet, the captain gave a pitch- up command to ensure that the MLG touched the runway first.

“At the last moment (around 10- 20 feet), the captain gave a nose- down input. This resulted in a negative pitch attitude during touchdown,” the document revealed. The regulator (DGCA) and the investigation board recommended that the pilot should be sent on correctional training. IndiGo CEO Aditya Ghosh admitted that the pilot had landed the aircraft on its nose wheel. He further claimed that all the recommendations made by IndiGo pertaining to the incident had been accepted by the DGCA.

“Indigo conducted an investigation and the inquiry board recommended that the captain should be sent on training to correct her landing technique. She was also advised to undertake a cockpit resource management refresher course as well as a route check. She has already undergone these procedures,” Ghosh said.

Significantly, the lady captain has earlier been counselled for a serious error in the go- around approach during a landing at the IGI Airport. Commenting on the incident, aviation expert Captain A. Ranganathan said: “The nose wheel can’t take the impact of landing. The pilot’s landing on the plane’s nose could have led to serious consequences. The episode shows there was a deficiency in training.” Former DGCA Kanu Gohain also felt that it was a very serious incident since the NLG is the weakest part of the aircraft and not designed to handle its landing weight. For the passengers, it was nothing less than a miraculous escape.