I dont understand how this is possible with GF as many airlines use the A 321 on 5 hour long flights with a full payload of pax + cargo. How is it that GF can only use this aircraft on 3 and half hour missions?
Because they went for the 'cheap' option of leasing 2 old retired RJ 321-100s. The range of the -100 is actually less than 320, however the new and improved 321-200s have more fuel carried in two optional ACTs. Their engines are also upgraded I believe.
The 100s had option of 'ACTs but the GF ones certainly don't have them installed. Of course the drawback with the ACTs is you loose cargo space...