I was just wondering what would make a flight showing as wide open in Economy and Business fill up so quickly that they had a full flight 24hrs later.

Carrier Flight From Depart To Arrive A/C St Availability
9W 121 LHR 20:45 DEL 09:45 +1 77W 0 F0 A0 C7 J7 Z6 I3 P2 Y7 M7 T7 U5 N5 L3 Q2 S2 K2 H0 V0 O0 W0

Above is the availability checked around 20hrs before the flight. Next day the flight was jam packed.

I have checked to see if any other flights got cancelled that day and nothing. Are Jet just showing a lot of cheaper classes to fill up the plane in the last few days?

I am an idiot. Post deleted.

I think that perhaps there is some misunderstanding regarding how an availability display works , it is not cumulative , ie , if you see

Y7 M7 T7 U5 N5 L3 Q2 S2 K2 H0 V0 O0 W0

that does not mean that there are 7 + 7 + 7 + 5 + 5 + 3 + 2 + 2 +2 ( total 40 ) seats unsold in the economy cabin ( in fact with overbooking practices it does not necessarily mean that there are any seats unsold* ) - the odds are that if someone booked 2 K class seats the Q and S would also disappear and possibly some of the other subclasses would reduce in number . So the number of seats 'available' for sale might have been a much lower number than first glance would indicate.






*Back when I was in the industry I can recall talking to an 'insider' at an airline with whom our company had a close relationship - the availability display showed quite similar to the one above , however , the flight was already oversold by about 50 seats - this was on a sector with a very high historic no-show rate , sure enough my pax reported that on his flight there were several empty seats

Yep, I know that if it shows 7 + 7 + 7 + 5 + 5 + 3 + 2 + 2 +2 that doesn't mean that 40 seats are empty in Economy.

See what I understood from this (F0 A0 C7 J7 Z6 I3 P2) was -

First is sold out and has no seats. Since I and P are showing 3 and 2 seats for sale and C J & Z are showing the maximum allowed (7) I had assumed that Business is more or less empty as they are showing I & P which is their lowest booking classes for Premiere.

Now if the same flight shows this F0 A0 C2 J2 Z0 I0 P0 I think its fair to assume that the flight is running on heavy load. As they are only selling 2 seats at a time in business and the lower fare business is sold out.

But my original question was that a flight showing C7 J7 Z6 I3 P2 in the morning at 10am and at check in there are no seats free in business.

Also (K) class is one of the lowest fares on the LHR-DEL route. So if an airline is showing one of the lowest booking classes available then I would have thought its fair to assume that the flight is running on low load?

So is Jet opening lower class seats at the last minute and successfully selling them?

Whoops. I was mistaken for the past 3 years. My bad.

sorry about that , it wasnt quite clear to me from your original post that you understood how an availability display works . ( and it is something which , in my experience , is often misunderstood )

with regard to your original question I can only say that even airlines themselves can be puzzled by how loadings change - when travelling subload I would sometimes get on flights that 30 minutes earlier I had been told ' not a hope' and conversely I would be bumped from flights that I had been told to expect 'wont be a problem' . In some cases ( and I am not saying that this is the case with your flight ) all it needs is a large family group travelling for an unexpected bereavement to change the picture completely and in other cases a late mechanical problem with a competitors flight on the same route can make a last minute difference between an average load and a full one .

Indeed. Airlines have very good data mining ability to obtain "average" loading profiles. Of course, using an average only means that you always wrong, just that half the time you are wrong by oversale and the other half by undersale!!!

Thats what I had originally thought so I checked all other flights that day to DEL and they all left on time.

Reason why I ask is that I fly quite often on this route and sometimes I need to cash in some vouchers for an upgrade. So if an empty flight in the morning turns up to be fully booked by the evening that doesn't give me much hope for upgrading.

It is common practice for some carriers to open all / many classes of availability on a flight 1-2 days before departure in the hopes of selling remaining seats.

I presume inventory in all classes is opened (rather than just higher Y/B) so that people using any combination fares can take advantage of it.

I had also accounted for that too. I was checking this particular flight for 7 days before hand every day and it was always showing similar seats as the morning of the flight.

This is what I am finding really weird. What happened to make the flight full or are Jet selling cheaper seats to get the bookings in?