The story
Stretch a 767-200 by 21 feet and you get the -300, which first flew in January 1986 with Japan Airlines as launch customer. The longer-range -300ER followed and became the most popular 767 of all, with 583 built. This code covers the whole -300 line, so the one overhead might be a Delta or United -300ER crossing an ocean, or a 767-300 freighter in FedEx, UPS or Amazon colors.
From the outside a 767-300ER looks identical to a plain 767-300. The ER's extra range comes from more fuel tankage and higher takeoff weights, not a different shape.
Quick answers
How do you identify a Boeing 767-300?
A slim widebody with two engines and four-wheel main gear bogies. The -300 is the long 767 at 180 ft, noticeably longer than the -200. Many passenger -300ERs wear tall blended winglets. No cabin windows means a freighter.
What does a Boeing 767-300 sound like?
A steady, deep roar on climbout. At night, often a freighter running heavy.
How many people does the Boeing 767-300 carry?
Typical configuration: 261 (2-class, -300ER).
How far can the Boeing 767-300 fly?
Range is about 5,980 nmi (-300ER).
How big is the Boeing 767-300?
It is 180 ft 3 in long and 156 ft 1 in across the wings.
When did the Boeing 767-300 first fly?
Its first flight was in 1986.
How many Boeing 767-300s have been built?
960+ (all -300 versions) built.
How rare is a Boeing 767-300 in Bogey?
UNCOMMON. Not rare, but not every day either. Worth looking up for. Your first Boeing 767-300 catch is worth 50 points.

