Pakistan plane crash in Karachi – important questions

A Pakistan plane crash happened in Karachi when a PIA lane crashed in a premium residential colony.

PIA has been beset with issues for a long time now.  In fact, interestingly in one of the flights in 2017, a PIA flight had taken 7 extra passengers to travel by standing in the aisle – just like the local buses in Pakistan.

As the video discusses, many reports and studies had been sharing concerns on the status of the PIA’s inefficiencies.

Pilot’s last words: ‘May Day! May Day! May Day!’ And then silence. 99 passengers+crew were flying Lahore to Karachi Two miraculous survivors found so far.

Here is a video from a CCTV camera which shows the last few moments when the crash happened.

Survival and death in Pakistan plane crash

While most of the passengers of the flight have died, there seems to have been one miraculous escape for Zaffar Masood, President of Bank of Punjab.

Among the dead is a popular model and actress.

Pakistan Plane crash – Questions

The plane that crashed had been in use for quite some time.  Its CFM56 engines are know to be workhorses and a best selling one.

Airbus said the plane had logged 47,100 flight hours and 25,860 flights as of Friday. The plane had two CFM56-5B4 engines.USA Today

Generally, these engines need to go to the shop for servicing around 30,000 or 50,000 flight hours depending on which fleet the aircraft is from.  So, it was close to its servicing time.  PIA aircrafts, remember, have had a very poor record of service.  It was just in 2007, that EU had barred 75% of the PIA planes to even come to Europe!

This tweet from someone related to Pakistan Airforce may have some clue.  APU is the auxiliary power unit.  IDG is integrated drive generators.  There is one IDG per engine.

How is IDG and APU related to the engine failures?

Each IDG is able to deliver 90 kVA, a power which is sufficient to feed all systems in the aircraft. As electrical power is vital, a second source is provided and each source feeds half of the systems, but is ready to take over and feed all systems in case of failure of the counterpart. When one IDG is off, the auxiliary power unit (APU) is used as a backup for the second source. The APU delivers both hydraulic power and electrical power. (source)

If both the engines fail it can be because of many issues – loss of fuel being one.  But even when the engines fail, the plane can still glide.

An aircraft will glide perfectly well even if all its engines fail. In fact, the chances are that if you’ve flown in a plane, you’ve seen it glide at some point (more about this later). Aircraft are able to fly through the movement of air passing over the wings. As long as this process continues the aircraft will continue to fly. If both engines fail, the aeroplane is no longer being pushed forwards, therefore in order to keep the air flowing over the wings, the aircraft must exchange energy through losing altitude to maintain forward airspeed. The aircraft doesn’t have to lose altitude particularly rapidly to keep flying and therefore it both engines were to fail a high altitude, the aircraft may have as much as 20 – 30 minutes aloft to find somewhere to land.Flight Deck Friend

The Pakistan plane crashed in the last few feet.

Pakistan plane crash – the crowded approach

This is precisely what the pilot of the plane was trying to do.  Do you see how close the flight was to the start of the runway.

The pilot missed the runway by just a little.  And, the reason why his approach glide failed was that the residential houses almost extended to the very last point.  Why?  And, Model Town in Karachi is supposed to be one of the poshest residential colony in the country.

A plane can glide for 20-30 minutes and then land.  As dangerous the situation is, its not that unheard of.  That it became such a difficult thing for the poor pilot and it led to so many deaths shows that there may have been something else at play here.