UAL747DEN From United States of America, joined Dec 2003, 2392 posts, RR: 12
Reply 2, posted (9 years 11 months 1 week 5 days 21 hours ago) and read 7040 times:
I believe that the ER is achieved by doing very little changes, and mostly just within the computer and in certification. The LR represents major changes to an aircraft and actual engineering changes being made so that the aircraft has an entirely different use.... Hope I was able to explained it somewhat understandable, and I could be completely wrong Who Knows!!!