Why is engine type displayed in cockpit?

[Russells]

I was looking at a cockpit video of a 737-200 approach and landing in Cancun, Mexico. At one point I noticed that the there was a name badge with JT7D-17A on it shown in the cockpit.
Why would this be displayed? Is it something to do with reminding the pilots regarding particular in-flight procedures with this type of engine?
regards
Russell

[BOAC]

Where several different engine mixes are available (737-200) it is helpful to know which one you have on which pylon.

[A30yoyo]

JT8D-17A surely?

[ONE GREEN AND HOPING]

This actually can be quite important in cases where different engines, or even different upgrades of same engines are fitted.

At one point in the company that I and many other people who enjoy this website worked for, we operated something like 13 variants of 747, and with three different engine types. The decals were important reminders of vital and differing limitations. For instance, the maximum internal engine start temperature before chopping the start cycle was very different between a P&W engine on a 100 series aircraft, and a two spool GE CF6 on a 200 series.

Limitations of all sorts were mandatory memory items, but those in other areas might be more obvious. It was not unusual for it to take more than one attempt to start an engine within temp limits, so it was important for both pilots and the F/E to revise the markedly different cut-off numbers......melting a whole engine was potentially quite simple, and frowned on by management.

The 400 series in many ways seemed much simpler all round, but we no longer had a Flight Engineer with his third set of eyes and ears.

[Flightmech]

Not sure but you may also have different dash numbers of JT8D on each wing? I know the '27 could have a mish-mash.

[Chris Scott]

It's not just a question of different limitations - important though they are - but one of performance (thrust). Different engines = different aeroplane.

Think of the take-off performance calculation, for example. There will be different charts/tables/database for each engine type and variant.

[eckhard]

The BA 747-400 fleet used to have a mix of RB.211-534G and -534H engines. The H had a higher thrust rating for take-off. There were two decals on the main instrument panel (one in front of each pilot) saying, 'This Aircraft is G-rated' or, 'This Aircraft is H-rated'. As Chris Scott points out, we had to be sure to use the correct charts for calculating take-off performance.

We also checked that the FMC had the correct engine rating by comparing the decal to the data on the Initialisation page.

A few years ago, all the engines were modified to 'G-rated' and now they are progressively being further modified with Trent cores, which makes them 'GT' rated. Same thrust as the 'G' but lower EGTs and fuel burn, so no need for the decals anymore but they're still there!

[Russells]

right you are - JT8D-17A
thanks to all for all the replies

[dubh12000]

Thats correct Flightmech, you could have a mismatch on the aircraft. e.g. a -15A on one side and a -17A on the other.