This insignificant effect is most likely due to customer expectations to low cost airline services (including physical factors) is also low(Noor, 2005).
As a consequence, low cost airlines customers do not have a high expection on physical element of airline.
As a result, the use of relatively old aircraft will less likely affectcustomer satisfaction in low cost airlines.
In contrast, as they have a higher serviceexpectation, physical conditions such as the modernity and the age of aircraft greatly affectthe level of customer satisfaction in full service airlines (Lawton, 2002).