A 738 burns approximately 21.20 kg fuel per passenger on a 90-minute sector. A 788 burns,
depending on configuration between 21.45 kg per passenger and 33.0 kg per passenger on a 90-minute sector.
Given Qantas in economy have a 30-inch pitch seat, a higher density is likely, bringing the fuel per passenger close to that achieved by a Jetstar 788 of 21.45kg per passenger. Of course you are correct there will be a small fuel saving, but to achieve that small ‘saving’:
- · Qantas require nearly 4 738 to uplift the same passenger count. ( Or maybe a B717 instead of the fourth B738-Interestingly the hourly cost is almost the same)
- · 8 pilots not 4 are required
- · 8 engines, not four are required
- · Assuming that the configuration is greater than 216 passengers, the 788 or alternative twin aisle will require 8 flight attendants (16 in total) as detailed in CAO 20.16.3, Qantas can, fly with 4 flight attendants on the 738, although often times they carry an additional flight attendant. Thus they require 16 flight attendants spread over the four 738 aircraft.
- · Four gates, dispatch staff and engineering support are required, in both Sydney and Melbourne.
- · Four aircraft are now squeezed into the airspace that two could occupy. Of course the same congestion applies to the check in, baggage and tarmac space.
- · There are four invoices totaling somewhere in the vicinity of $2,700 per hour, not two.
Currently the Qantas A330 domestic configuration can deliver 297 passengers at around 26.5 kg of fuel per passenger. Again the airspace is less congested, less pilots are needed and if less than 100% load factor is achieved on the 738 Qantas still need to squeeze four of them in the airspace and on the gates.The yield and revenue mix is difficult to quantify outside fort fumble, but our guess would be that the premium seat would yield significantly more in Qantas livery than Jetstar
Depends on their focus. If management talk about fuel (isn't it a DFO KPI?) and exclude all other practical considerations, then sure thing, shut down an engine when sitting at a holding point as the three aircraft in front wait to cross the same intersection. Naturally departures may also be sequenced off the active runway, so you may be a while. Of course having crossed the intersection, kindly wait for the occupied gate to become unencumbered so that your aircraft can enter the same apron, fourth in line.
Qantas need a new fleet.