A321 reverse thrust noise etc.

[Crosswind Limits]

Hi,

Last night I returned to LHR on a domestic flight. It was my first flight on an Airbus 321, although I have flown on A320s and A330s before. The landing on 27L was firm but appeared safe but what then followed was the biggest racket I have ever heard in the cabin due to reverse thrust! :eek: Now I know I am not a jet pilot but I am a part time instructor who has studied upto ATPL standard, so consider myself more credible than most pax. What I find most unusual (I wasn't alarmed) was the noise appeared throughout the cabin and not just over the engines and the overhead compartments and ceiling vibrated so much I thought to myself this can't be normal! :confused:

I believe we vacated quite far down 27L and therefore my only possible explanation is that it was a late touchdown which required considerable reverse thrust.

Cheers! :)

[Tommyinyork]

Flying on a Monarch A330 i have to say that has the loudest reverse thrust. I have been on an Air 2000 A321 and i have to say the reverse thrust on that plane was quiet.

[Groundbased]

Not a pilot, but.

In some cases reverse is not planned for and not used; pretty quiet. It ius my understanding that pilots have a choice between idle reverse up to maximum reverse. Presumably this will mean varying levels of noise depending on how much reverse is used.

[Justbelowcap]

The reversers have little effect on stopping distance (with auto brake) as the brakes will slow the aircraft down at a set decelaration. All the reverse does is to take the pressure off the brakes.

The brakes get very hot, as they work so hard, and to cool them down Airbus have fitted some brake fans. When these are not working sometimes the brakes don't have enough time to cool down to be below the 300deg needed to take off again. So if the fans are not working then the crew might have elected to use full reverse and a long roll out to reduce the brake temperatures on landing.

[HolyMoley]

Sorry, but that's not completely right. The (full) reverse thrust on the 320/321 is loud and it does shake the bins etc overhead. That's normal, but it is right that you'd use full reverse to save the brakes, but also rare that you'd use idle too. You certainly wouldn't get away with a long roll-out at LHR unless it's the middle of the night!

[Justbelowcap]

A long roll out at LHR is not a problem. Don't confuse a long roll out with RW occupancy time. Nobody is going to go too far down 27L unless they are going to the cargo apron. With the brake fans u/s it's pretty standard to use full reverse on a hot day with a short turnaround. The turn-offs at LHR are having some work at the moment so if you miss N5E you have to carry on to N6E but was trying to demonstrate that some times the crew use full reverse for operational reasons rather than to make up for a mistake.

[Max Angle]

SOP at our lot is to use max reverse for every landing (don't ask why, it's a long story!) unless banned for noise reasons. Yes it is bloody loud in the cabin and the bins all shake etc. It could be made a lot quieter by using a little less than max. but nobody in management land seems interested in changing. Brakes do get very hot if you don't use any at all but max. everytime is just daft IMHO. It doesn't affect brake wear as carbon brakes wear about the same regardless of how hard they are used, it's the application of the brake that wears it out rather than the intensity of the application.

[Crosswind Limits]

Thanks everyone for your input. I suspect I may have flown with your lot Max Angle! :cool:

[Spearing Britney]

For the sake of completeness not all operators have the brake fans fitted...

As such some operators are very likely to use max on 'less than long' runways

[EasyBaby]

Allthough I have not been on either the A320/321 our company uses the A319 (im guessing here thats its similar) And our SOP for Cabin Crew is to advise the pax on the noise created by the reverse thrust on our descent PA, i think we do this as most of our pax are used to the 737 and the extra noise could be a little alarming but i dont know if we would do the PA if we were a sole A319 operator.

Cheers
EB ;)

[earnest]

Max Angle,

Our company changed a while ago to using min reverse based on that logic (which I'm not arguing with, by the way - that's the "techies" tell it and how we are taught to understand it). After a while they changed back to max reverse because it did turn out to be causing more frequent changes of brake units. Don't know why. If only it was all black and white, eh, and exactly like it says in the book?

[Max Angle]

Yeah, despite what the brake and Airbus people say I suspect that regular very high brake temps don't do the units any good. There is a massive difference in temp. when you don't use reverse on a heavy aircraft but just using a little less than max. makes a big difference to the noise in the cabin. As you say, it's not black and white and various airline SOP's probably leave something to be desired as well.

[p.savage]

Ever landed at BHD on a A321, they sure don't like our short runway. Now, thats braking!

Cheers
Savage