Did low visibility play a role in the crash of the Learjet 45XR aircraft near Baramati airport that killed Maharashtra deputy chief minister Ajit Pawar and four others on Wednesday?
CCTV footage from near the airport shows the plane banking steeply at a low altitude before crashing. Aviation experts and pilots The Telegraph Online spoke to pointed out that this is “possibly because the pilot was misaligned with the runway and realised it very late.”
The real reason behind the crash cannot be ascertained until the black box data have been recovered and analysed, a number of pilots and aviation experts stressed.
All of them underlined that the conditions under which the pilot tried to land were far from ideal.
“The Baramati airport doesn’t have any Instrument Landing System [ILS], runway lights or a beacon,” former Indian Navy test pilot K.P. Sanjeev Kumar said. “So, the only way you can make an approach is by visually spotting the runway and then aligning yourself visually on an approach which will lead you onto the runway.”
IAF Group Captain Sivaraman Sajan echoed Kumar, saying, “The pilots rely on visual cues and what is fed into your system through GPS coordinates and everything. So you head towards the coordinates that you fed as a runway, and you extend an imaginary line from that and along the runway direction, and fly in towards it and hope you will pick up the runway.”
Usually, the pilot feeds in the coordinates of the runway from Google Earth into his system. He then extends the centreline and plots another point. The pilot then navigates to that point and that’s how they know they’re on the right track.
They keep checking to have a rough estimate of distance and altitude. However, the runway should come into view at a particular time. Sometimes, pilots push beyond that particular time and hope they pick up the runway. If they don’t, the situation gets tricky.
According to the Union Ministry of Civil Aviation, the crew of the ill-fated flight was informed that the visibility was 3,000 m. Experts point out that for a visual approach or Visual Flight Rules (VFR), the ideal visibility should be more than 5,000 m.
Sajan said that the pilot can invoke a special VFR and still attempt to land even if visibility is less than 5,000 m.
However, the visibility of 3,000 m is not determined by a meteorological officer but by pilots from the local academy who man the tower. According to Kumar, “the lack of Met instruments means the visual range being provided by the tower is an estimate.”
He added: “This visual range is from where the person manning the tower is. From where the pilot is, the range could be different.”
This is made worse by the fact that the aircraft was facing east while landing, which meant that it was “landing into the sun”. The direct sunlight, aided by fog, reduces visibility.
“If the sun is on your face, you will not be able to see. If the visibility is 3 km, you will not be able to see 2 km either because the sun is on your face,” said Kumar
Experts note that the “only safe way” to make a visual approach at an airport like Baramati is by to do it in fine weather, which is “more than 5,000 m visibility and being aware of the ground.”
It must be noted here that the captain of the aircraft, Sumit Kumar, had landed at Baramati airport multiple times before.
On January 28, the aircraft reported the final approach of Runway 11, but the runway was not in sight, prompting them into a go-around. The next time, the crew did report the runway to be in sight but did not give feedback on the landing clearance.
Experts point out that the Learjet 45 is one of the fastest jets in its category, and according to flight data, the amount of time taken for the go-around is too short for weather conditions and visibility to change.
The pilots, a number of experts said, were most likely making the second approach in the same conditions that they tried to make during the first approach.
Had the second approach failed, the pilots would have had to divert to a secondary airport for landing.
A number of sources told The Telegraph Online that there is often direct or indirect pressure from VIPs – who mostly hire charter aircraft – to land, which prompts pilots to attempt landing even in not-so-ideal conditions.
They further said that private charter services often operate by a different set of parameters in comparison to commercial flights; if a private charter flight doesn’t land at its intended destination, the aircraft crew don’t get paid.
When an aircraft like a Learjet is on short finals with its landing gear and flaps down, it is very difficult to steer because the aircraft is locked in to land in a straight line and at a low speed. So, if the pilot was not aligned to the runway and realised it late and tried to steer towards the runway, the aircraft would have resisted.
Kumar said, “If you do any kind of sudden manoeuvres at a low height, then it is very unforgiving.”