Boeing 737 - Question about firm landing

[frnikolai]

Hi,

I flew back from Stansted to Madrid around a week ago, and something has been annoying me since I touched down in Madrid

The plane felt as if it was coming too fast, and moving about a bit. And as far as I can tell, it was very good weather!

Then the wheels seemed to smash into the ground and the plane felt like it came in hard?

It was a Boeing 737-800, and I have flown on this a lot, and never has it ever landed like this.

A loud bang, the overhead lockers rattleing, and a hard feeling.

This was so scary, as I though landing wheels would collapse, snap, and break.

I would be very interested to know why do sometimes planes do this, is it a pilots mistake?

It was with Ryanair, and from a search, it seems this is often. Although this is my first bad landing with them, I still fly with them.

I am NOT saying Ryanair are bad or criticising any pilot. I can't fly a plane, so I trust my life with pilots.

I would be extremely grateful for someone to explain exactly what went wrong, or what happened. And how much the landing wheels can take before they will snap and break.

Thank you.

Nikolai.

P.S

I am not suggesting Ryanair are a bad airline or saying the pilot was very bad.

[montag]

The trouble is that only someone on the flight, or a maintenance engineer called to inspect the aircraft afterwards could tell you whether that landing was normal, firm or heavy. Certainly if the landing was too heavy the aircraft will have gone nowhere afterwards without a maintenance inspection. Firm landings are common and can occur for a number of reasons. Heavy landings are quite rare.

The landing gear will take a great deal of abuse before there is any danger. You're far more at risk is any misstowed hand luggage decides to fly around.

Did the aircraft burst any tyres?

[forget]

Ignore this guy, he's a wind-up. Another of his posts from the 23rd January

Thank you, BOU-PAX. As you seem to fly from there a lot, how are the landings and take-offs? From a review I read they seem to be semi-crashes. I heard they had to hit the ground really hard to be in room to stop...

Thanks.
Nikolai

[dwshimoda]

The plane felt as if it was coming too fast, and moving about a bit. And as far as I can tell, it was very good weather!

OK - I'll bite!

So Nikolai, you are familiar with the concept of Vref30 +5 and gust factor? (Apologies if this isn't entirely correct for the B738, but I assume it's at least similar to the B752) You can gauge, from a sideways on seat with limited visibility, if the aircraft is coming in too fast? Presumably you could also work out the landing weight of the aircraft as well?

And a blue sky means there is no wind / windshear / gusts?

You know nothing. You may have experienced a firm landing - sometimes this is because of a pilot up, sometimes it is absolutely not their fault.

Please feel free to respond with your meteorological and pilot qualifications that allow you to post such .

DW.

[G SXTY]

Oh dear God, here we go again . . .

http://www.pprune.org/passengers-slf...-landings.html

[JEM60]

Give me a firm landing rather than a long, long extended float down the runway any day. I want to be touched down at the beginning of the runway, not the end!!! Aircraft are much stronger in the undercarriage department than passengers think, and getting the aircraft on the ground is more desireable than a float, because it gets the anti-lift devices, reverse thrust etc. going nice and early. Judge landings from the Flight Deck, not from the passenger cabin!!

[montag]

You know nothing.

This is probably entirely true, but also entirely the wrong answer to give to a possibly nervous passenger who was concerned about their safety. Unless you subscribe to the 'shut up, sit down and be grateful' school of customer service.

It's unlikely the landing was unsafe. If frnikolai had an opportunity to speak to one of the cabin crew before disembarking, maybe they could have given some reassurance. With short turn around times there might not be the opportunity though.

[keltic]

Was it hard indeed, or you simply thought it was?

I have flown dozens of times with Ryanair, and I have never had any weird landing. Some are better than other but nothing particurly scary. Madrid is particularly notorious for the turbulences in landing in hot days.

[Rainboe]

You cannot judge speed from the passenger cabin! Period! So make no accusations there, please!

I always explain, and you can find it in the other thread, but the 737 has a very firm main undercarriage with little give. It is very hard to put it down softly. Every arrival is a thump. I don't know why it is like that, Boeing will know. I have flown it for 10 years. You can land the 747 and the 757 so soft nobody can feel it, but every arrival in the 737 is like there is no suspension at all. So a firm arrival feels like a bad landing. It's not- don't worry about it- they do it every day.

[WHBM]

Originally Posted by Rainboe

the 737 has a very firm main undercarriage with little give. It is very hard to put it down softly. Every arrival is a thump. I don't know why it is like that

Possibly a feature of the single-axle 737 undercarriage whereas the 747/757 have twin-axle bogies and a necessarily more complex suspension. The Tupolev Tu154 has a triple-axle bogie and is even more so, every landing I have ever had on it has always been a greaser. In fact, Russian pax who have been familiar with the 154 for years comment adversely on the landing thumps of the 737s now coming into general use in Russia. We here know it's not an issue, but it's still a thump.

[angels]

You walked away from it. Ergo it was a good landing.

[montag]

The plane has flown again? It must have been a great landing!

[Rainboe]

Possibly a feature of the single-axle 737 undercarriage

Yes, I agree, but I notice the A320 series don't arrive with such a thump. I would have thought it was important to design in a softer undercarriage, and not just for softy passenger reasons. It must stress the fuselage thumping in 40-50,000 landings over an airframe lifetime. You can see the effects in the fuselage aft of the wing- wrinkling developing. Then you get more of the 'Indonesian' type landings where the fuselage collapses altogether either side of the wing- something I don't think an A320 series has experienced at all, but several 737s are photographed in that state!

[lastgasp]

Montag

Re: Cabin crew giving re-assurance - I recall a really bad landing (I won't mention the airline) when we were clearly too hot over the threshold and I was convinced we would have to go around again. But no, we were plonked down with a huge bang that caused screams from pax and then decelerated with a force I have never encountered before or since.

PA announcement from the senior stew " Ladies and gentlemen, you cannot have failed to notice that we have just landed at Stansted"

[G SXTY]

we were clearly too hot over the threshold

Please understand that you cannot - repeat CANNOT - judge the speed of an aircraft by looking out of the window. I can't and I fly them for a living.

That's what the airspeed indicator is for.

[Final 3 Greens]

G SXTY

Please understand that you cannot - repeat CANNOT - judge the speed of an aircraft by looking out of the window. I can't and I fly them for a living.

Agreed.

What about perceiving RoD though?

I was a pax on an A320 into Frankfurt last year and we ended pretty high on final (in fact the gear went down whilst on base), with what felt like a very uncomfortable deck angle (i.e. with the nose pitched down) and the houses getting bigger at a noticeable rate for a minute or two, before a more usual attitude was established.

I'm not suggesting that the aircraft was being flown in any way outside it's operating limits, just nearer to the edge than usual.

Although I have never particularly noticed a difference in perceived groundspeed on the same type of aircraft, I did percieve a substantial difference in the RoD on this flight - it felt approximately like an approach into LCY or a glide landing in a light single.

[Dit]

What about perceiving RoD though? ........ I did percieve a substantial difference in the RoD on this flight - it felt approximately like an approach into LCY or a glide landing in a light single.

Have you thought that the feeling of a high RoD (probably caused by a perception of a nose down body angle) may have been an illusion?

Due the cost of fuel we plan to do an idle descent, now if you get a short cut this can mean the only way to get back onto the vertical profile is to use the speedbrake and increase the speed. In doing this the a/c can pitch down a little aggresively. It may well be that when the pitch angle was brough back towards level it was at a much slower rate (which would be hard to detect in the cabin without a horizon to judge it from) thus your body didn't detect it. Thus the illusion of a high RoD.

[Final 3 Greens]

Have you thought that the feeling of a high RoD (probably caused by a perception of a nose down body angle) may have been an illusion?

It wasn't an illusion, there were plenty of ground features to relate to and I am an experienced visual pilot (several hundred hours) as well as having paxed on hundreds of airline flights, so I know what is normal and what a steeper descent looks like.

It may well be that when the pitch angle was brough back towards level it was at a much slower rate (which would be hard to detect in the cabin without a horizon to judge it from) thus your body didn't detect it. Thus the illusion of a high RoD.

No, this was at low level and the aircraft was pitched up smoothly, but firmly after the initial high descent - they did use the speedbrake from rolling out onto final to the point where the aircraft was pitched to the usual angle prior to landing.

[TightSlot]

I've amended the title of this thread to try and move some of the combustible materiel away from the heat source.

frnikolai - Your question is covered in the forum FAQ - did you read it?

[dwshimoda]

Montag

This is probably entirely true, but also entirely the wrong answer to give to a possibly nervous passenger who was concerned about their safety. Unless you subscribe to the 'shut up, sit down and be grateful' school of customer service.

Then he / she should phrase the posting appropriately. I don't subscrive to the "shut up, sit down and be grateful" school of customer service at all. I do however try and give my pax the smoothest possible ride - but sometimes the landing is way firmer than I would like - sometimes it's me just not catching it right, sometimes it's one of any other number of factors.

I would never, never, go and post on on a different forum a similar statement. Imagine on the Professional Doctors Rumour Network (if it exists!) me posting "Tonsillectomy - very badly stitched afterwards" I wouldn't be so presumptious nor crass - I would ask if what I experienced was normal, and if so why that might be. They are the professionals, not me, so I would alue their input / judgement to help me learn.

And Rainboe is spot on - I defy anyone to judge speed from the passenger cabin - I can't even do it from the FD which is why it is part of my scan almost every second during approach / landing.

DW.