Some additional examples, where using the FAA exit limit falsify the actual cabin space of an aircraft.
1, B747 classics vs. 747-400:
In AE Boeing 747-100, 747-200 series has "550 seats capacity" vs.
Boeing 747-400 series has "660 seats capacity".
In the reality: passenger capacity increased by only 10 percent by extending the upper deck and relocating the new straight stairway to the rear of the upper deck. There is no 20 percent cabin space difference between these aircrafts.
2, B747-400 vs. 747-8I:
In AE Boeing 747-400 series has "660 seats capacity" vs.
747-8I has "605 seats capacity".
In the reality: The 747-8 Intercontinental is the only jetliner in the 400- to 500-seat market, stretched 5.6 m (18.3 ft) from the 747-400 to provide 467 seats in a three-class configuration and a 14,815-km (8,000-nmi) range.
So the 747-8I actually has bigger cabin space just the company not certified it for bigger passenger number.
747-400 typical 3 class configuration 416 seats
747-8I typical 3 class configuration 467 seats
With 51 additional seats and 26% more revenue cargo volume than the 747-400, the Intercontinental was designed for the heart of the premium market offering more range, more payload and more fuel efficiency than any previous 747.
While in AE a 747-8I is 10% smaller than the 747-400, just because the FAA exit limits....
3, Narrowbody Boeing 737-800 vs. A319-100:
Boeing 737-800 has a 189 seat FAA exit limit, but this is not limited by the actual cabin space, the exit door capability limits this value.
If you check the following seatmap from Ryanair, you can see that they have 30" seat pitch and still have one galley in the passenger area. So this plane has bigger cabin space than the FAA exit limit.
http://www.seatguru....ing_737-800.php
A319-100's 160 seat exit limit matches the possible max. seats (at just 28-29" pitch) and the actual cabin space:
http://www.seatguru....Airbus_A319.php
Because of this, if you are using two or three class configurations the relative productivity will be much better for an A319 vs. B738, or 747-400 vs. 747-8I / 747 classics.
4, The whole A350 series is affected too
This series intended for long range use, so the FAA certificate is declared for fewer passengers, and does not match with the actual cabin size and the Airbus recommended two class seat capacity.
A330-300 as reference:
cabin width: 5,28 meters
cabin lenght: 50,35 meters
Airbus recommended seat capacity (two class): 300
FAA exit limit: 440
A350-900 with approx. 10% larger cabin space than the A330-300
cabin width: 5,61 meters
cabin lenght: 51,8 meters
Airbus recommended seat capacity (two class): 315
FAA exit limit: 420
A350-1000 with approx. 20% bigger cabin space than the A330-300
cabin width: 5,61 meters
cabin lenght: 58,8 meters
Airbus recommended seat capacity (two class): 369
FAA exit limit: 450
An example how the quoted additional cabin space parameter would handle these aircrafts:
-Boeing 747-100/200 series:
maximum allowed passengers: 550
cabin size: 605
-Boeing 747-300 and 747-400 series:
maximum allowed passengers: 660
cabin size: 660
-Boeing 747-8I:
maximum allowed passengers: 605
cabin size: 726 (from the cabin size improvement compared to 747-400)
-Boeing 737-800:
maximum allowed passengers: 189
cabin size: 200
-Airbus A319:
maximum allowed passengers: 160
cabin size: 160
-Airbus A330-300 as reference:
maximum allowed passengers: 440
cabin size: 440
-Airbus A350-800:
maximum allowed passengers: 360
cabin size: 405
-Airbus A350-900:
maximum allowed passengers: 420
cabin size: 462
-Airbus A350-1000:
maximum allowed passengers: 450
cabin size: 541