COMMONALITY BETWEEN AIRCRAFT
Aircraft operators and pilots often refer to “commonality.” This refers to aircraft having the same type rating – where different aircraft from the same manufacturer share the same rating. Pilots are able to fly these aircraft with just minimal conversion training rather than a new license rating.
KEEPING AIRCRAFT THE SAME – THE TYPE RATING
Commonality between aircraft has been an issue for decades. Manufacturers have long tried to keep aircraft as similar as possible to minimise the training needs to convert pilots. This is formalised through the issuing of type ratings by civil aviation authorities.
To approve aircraft under the same type rating, authorities need to be satisfied that the aircraft have similar design and operating characteristics. The cockpit layout is essential in this, as is how aircraft handle and perform for the pilots. This is how new aircraft, with updated features, materials, and engines, can still be covered by the same type rating as older aircraft (the long history of the Boeing 737 family is the best example of this).
Commonality is very important to airlines and other aircraft operators. They want pilots to be able to fly aircraft across the fleet and minimise training to move to new types. It also, of course, has benefits in scheduling and maintenance.
COMMONALITY WITH BOEING AIRCRAFT
To consider some real examples of commonality, we will take a look first at Boeing’s aircraft. All the Boeing 737 aircraft (from the Original Series of the 1960s up to the MAX Series today) share the same type rating. Minimal conversion training is needed for pilots to move between types, and this has been a huge advantage for Boeing over the last 50 years or more.
It currently faces a major issue here with the new 737 MAX 10 aircraft. If it does not receive its certification by the end of 2022 (which is unlikely), it may need changes to the cockpit warning systems to meet new regulations. These are likely to be significant enough to warrant a new type rating, destroying commonality with other 737 aircraft.
The Boeing 757 and 767 share the same type rating. This is unusual for a narrowbody and a widebody aircraft and reflects the fact that the aircraft were designed together and share much in common.
The Boeing 777 and 787 are slightly more complicated. These again share much in common (with the 787 using many newer 777 design features), but only share the same rating in the EU. In the US, the FAA considers them as different types.
COMMONALITY WITH AIRBUS AIRCRAFT
The story is similar with Airbus aircraft. Airbus is probably a step ahead in cockpit commonality though, with most of its aircraft sharing a very similar cockpit. This minimises pilot training considerably, even when a new type rating is required.
For narrowbody aircraft, the whole Airbus A320 family (including both the original and the neo variants) share the same type rating. However, the Airbus A220 has a separate type rating. This is not surprising given that it was originally designed by Bombardier as the CSeries, before being branded by Airbus.
With widebodies, the Airbus A330 and the A350 share a type rating. The Airbus A340 and A380, unsurprisingly given their very different handling characteristics with four engines, have their own ratings.
COMMONALITY WITH EMBRAER E-JETS
Embraer has succeeded in keeping commonality through the whole E-Jet series. Its earlier Embraer Regional Jet aircraft have separate type ratings (one rating for each of the EMB-110, EMB-120, and EMB-145), but the E-Jets and the newer E2 jets all share the same rating.
BUSINESS JET TYPE RATINGS
Type rating are similarly issued for smaller twin-engine business jets, and again manufacturers try to keep commonality within the series. Major updates, or size increases, often lead to a new type rating. Some examples include (based on US FAA ratings):
- Gulfstream jets: Several jets share the same rating. The G300 and G400 are covered by the same G-IV rating; the G350, G450, and G500 have the G-V rating; and the newest G650 has its own G-VI rating.
- Dassault jets: The Falcon 7X, Falcon 10, Falcon 2000 all have their own type rating. The Falcon 50, 900 and 900EX share a rating, as do all Fan Jet Falcon aircraft and earlier Mystere Falcons.
- Bombardier Learjets: All current aircraft, except the Learjet 45 and 60, share the same type rating.
Commonality has always been important when operators are considering fleets. Having a streamlined fleet with the same rating has many advantages. For manufacturers, it can make the difference in aircraft selling success – as Boeing is finding out now with its latest MAX 10 aircraft.