Hard Landing In SFB

[PJ2]

Flight Detent;

The terms "hard" and "heavy" in the context of a touchdown seem to be interchangeable but I agree, the term "heavy" usually refers to near/at/over AUW.

A "hard" landing is defined in the AMM as a landing with a vertical acceleration of more than 1.75g at the c of g or a vertical speed of more than 600fpm. For an overweight (heavy ) landing, the acceptable VSI is reduced to 360fpm.

Vertical acceleration in 'g' can vary depending upon pitch rate change at touchdown (rotating NU due to a sudden pull on the stick in response to a high rate of descent), a/c weight, drift angle at touchdown, roll attitude and so on. Landings of over 2g's may not wrinkle fuselage skin depending on these factors.

Since no one has broached the topic, I would like to talk about the bogie-tilt on both the 330 and 340 series. While a touchdown on the rear truck can be very nice, depending upon spoiler deployment, reverser deployment, pitch rate (de-rotation manuever) and the usual environmental culprits, the second touchdown on the forward bogies can be very hard indeed.

The bogies are rotated, or tilted at an angle both during the takeoff and touchdown manuevers to provide greater tail clearance. The tilt is controlled both mechanically and hydraulically. This is separate from the 330/340's oleo shortening during retraction, which reduces the length of the oleos mechanically so that they will fit into the gear bay.

The subject of achieving a smooth landing on an Airbus A340/A330 is the topic of many discussions but what I fail to understand is, the design accepts some really hard touchdowns which for all intents and purposes are beyond the control of the pilot to reduce. Many times I've had it go on very nicely, with little remark from the front bogies but other times, after seemingly not changing the technique, it slams down. The '500 doesn't seem to do this nearly as much.

[fantom]

The bit, Mr Spotty, which implies the 330 is prone to hard and heavy landings.

[Mr @ Spotty M]

Thank you Fantom for clearing it up.

[RoyHudd]

Yep. The 330 is prone to soft landings, at least the maingear, in my pudgy little hands. Talk of hard landings is cobblers.

[PJ2]

RoyHudd;

I agree with you and with fantom...the 330 lands as smoothly as any large transport and is truly a joy to fly. It was the "bogie-unlock" phenomena giving the "second-landing" that I was wondering about. It doesn't happen all the time. And if you're not experiencing it either on the 330 or the 340, then I'd love to know how you're handling it and what's being done to avoid getting that bit of a thump when touching down because I haven't talked to anyone who's avoided it all the time. I'm not criticizing the airplane...it's a beautiful design, a great cockpit and a wonderful blend of automation. It's this one item I'm enquiring about...

Cheers

[guclu]

Well the main gear landing problem..........

If you land smootly the most rear gear then you have to bear in mind that the front rear gear is still way up in the air. And if your a/c is very light then you have to be extra carefull for the "second landing".

Well if you also marked it is more difficult to make a smooth "second landing" with a very light a/c. The problem is after landing the most rear gears if you just hold the sidestick back the a/c will fly until it can't fly anymore and will drop down from where it is and you will make the hard second landing.

I'm just smootly releasing little back pressure on the sidestick after a smooth first landing and with very small adjustments (release and back presssure cycles) let the main gears land but just wait a little bit for the reversers after initial back gears touch down unless you are landing a short rwy. When you feel that they are going to touch down this is usally 1-2 seconds after initial touch down then open the reversers and there you have second landing smoothly. It works for me.

[RoyHudd]

Ditto Guclu, gentle forward pressure momentarily after the rear gear has contacted, effectively landing the forward main gear wheels, thereafter landing the nosewheels, which can be trickier.

[Bernoulli]

Reading this thread just makes me deeply grateful to be flying the 767

[interpreter]

Bernoulli - me too. I like an aircraft that glides well!

[MarkD]

The A330 glides just fine - just ask Air Transat

[Off Stand]

So, is the a/c servicable or will it undergo repairs?

[Mr @ Spotty M]

Aircraft is having both main landing gears replaced.

[squeaker]

There is a specialist French car breakers on the A5 near Stanbridge, shall I check with them on the way home, just in case...

[ACMS]

Happened to CX in TPE a year or so back. Airbus were informed and initially said no worries. A day or so later they changed their minds. A/C needed a new gear.
I pax in the A330 to and from Oz a lot ( i mean 15 times a year ) and I hardly ever feel a smooth landing, the first touchdown is ok, but as the gear tilt the second touchdown is a real bump.
And watching other A330 landings from the fence or whilst taxiing in I see that all A330's ( from a lot of other carriers ) do the same thing, ie nice smooth touchdown on the rear wheels, seems to hover without tilting for seconds then crunch down on the front wheels.
Give me a nice 777 any day.

[unwiseowl]

Does anybody know what the circumstances were? Was PF capt or F/O? Was wx a factor?

[Smudger]

Christ, you lot, get a life.. If you are a commercial pilot you can't fart these days without getting the amateur third degree on Pprune. Get down the pub for Pete's sake.

[Sobelena]

So, tell me Smudger, how do you achieve a smooth 2nd fart?

[Smudger]

Sobelina

Years of practice my friend, years of practice.

Smudge

[hapzim]

Wx was good and experienced crew both seats.

[sdac]

3.2 g, allegedly. Quite heavy. Gear replacement comes in at 8 million, or so. Do Monarch require their pilots to repay that in instalments? Two Captains flying together; enough said.