It might be worth considering what your break even point is and work out an average ticket price from that, rather then setting a price and then trying to make the numbers work around that figure.

Load Factor
It’s probably reasonable to assume you can hit load factors of 95%+, many flyers look for the cheapest option and if you are that option you’ll get the business. I’ll use myself as an example, when I fly to New York or Washington I often use Icelandair – even though I have to stop off for 1:30 in Reykjavik, the return fare’s usually £200+ cheaper compared to the legacies.

When Norwegian Air announced it’s transatlantic service at the start of this year sales went through the roof, I think at it’s peak the airline was receiving a passenger booking for one of its transatlantic flights every 3 seconds… With this in mind, 95% isn’t far fetched and may actually be an under-estimate.
Just last month they extended that service to cover Gatwick with one-way fares to New York starting at £149… (an additional £30 option entitles you to 1 hold bag, a meal, and seat allocation). Although bare in mind this is the super off-peak fare booking over a year in advance, looking at a return flight in August 2014 you’ll be paying around £630 return (including the 2 x £30 option)… Which is still around £300 cheaper than BA for the same dates.

http://uk.reuters.com/article/2013/10/17/us-norwegianair-expansion-idUKBRE99G0EY20131017

Getting back on track, 95% of 290 seats is 276. I’ll use this figure for the basic calculations.

Fuel
I gave a figure of £29,000 previously, I’ll just give a run-down of how I got that. It’s very crude I’ll admit, but I’m sure it’s an accurate rough estimate.

The range of the 767-200ER is 6385 nautical miles. A 4000 nautical mile trip to the south east coast of the US is 63% of this.
The fuel capacity of the 767-200ER is 24,140 gallons. 63% of this is 15,208 gallons (presumably how much you need to do the 4000 miles?)
Currently the price of Jet-A fuel per gallon is around 302 cents ($3.02), which aquatints to 185 pence (£1.85).
http://www.iata.org/publications/economics/fuel-monitor/Pages/price-analysis.aspx

15,208 gallons x £1.85 per gallon = £28,134.80 (the price of fuel must have fallen since I last did the calculation :rolleyes: )

This works out at around £102 per passenger (based on the 276 load factor figure).

Lease
The 767 is probably one of the least demanded wide-bodies around at the moment (along with the A340), it’s fuel burn per passenger is simply too high for airlines to consider it as a viable option. However, this does mean you can lease them out on the cheap. I’d estimate a ACMI (aircraft, crew, maintenance & insurance) wet lease to be in the region of $400,000 a month, now assuming the aircraft can perform 60 sectors a month (2 a day). It’s around $6667 a flight, or £4080.

Per passenger around £15 (again based on the above 276 figure).

Airport Fees
£275.86 for an aircraft between 55-250 metric tonnes to land at Stansted (off-peak).
Fixed fee of £137.52 per departure.
Estimated parking charges; £225.
Miscellaneous ground charges; £400 (covering everything from removing waste-water, to paying for check in desks).
http://www.stanstedairport.com/media/4167/stal_conditions_of_use_%202013_14.pdf

(I’ll assume the fees are similar for your arrival airport in the US). Total fees: £1038.38
Average per passenger (276) = ~£4

Administration
All the behind-the-scenes work that goes into operating a flight, flight operations is a huge part of any airline – yet one of those things no passenger will ever see.

I’m going to throw it out there and say I don’t know! :stupid: Maybe £3000 per flight as an guesstimate including ground staff salary?

I’ll add another £4000 for the numerous little things I’ve bound to have neglected during my calculations along the way.

So forgotten entities + administration = £7000 (per passenger ~£25).

Totals
£28,134.80 + £4080 + £1038.38 + £3000 + £4000 = £40,253.18

Per passenger = £145.84

After including the £97.50 discussed in my first reply (APD etc.) that brings the grand total per passenger per sector to £243.34 (or £486.68 return).
You can bring this break-even price down as cloud_9 says through the sale of on-board products and luggage etc. So maybe a break-even price of £420 return isn’t unreasonable?
A 5% profit margin is reasonable, so sales price will be around £441.

British Airways LHR-MIA for October 2014 (I assume this is off-peak ish?) £698.75, obviously charter airlines will fly you there for less but it would appear I’ve just knocked £260 off the flag carrier’s price.

EDIT: I’ve just realised an error in my calculations; you don’t need to pay APD on the return leg. I believe the US equivalent is around £20. So instead of £441, the return fare will be around £394. Cheap as chips! 😮