Boeing 737 - Question about firm landing
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Speed versus RoD perception paradox
Rainboe
I think you may have misinterpreted my posting about RoD or I wasn't clear enough.
My point is that I cannot judge groundspeed at all, I get no sense of an approach being faster or slower, even though there must be quite a difference in aircraft types, weight, wind etc. All approaches to landing tend to be perceived as being the same by my senses.
I can't judge RoD either, in terms of 000 of feet per minute, but nearer to the ground (say 5-6,000 feet or less, with a clear horizon) due to the deck angle and the rate the scenery is growing, I find that I get a sense of normal (again, probably varies quite a lot in actuality) or unusual, e.g. LCY feels (or should I say more correctly looks) very different to LHR.
PPL training/VMC flying is nowhere near the standard of professional training or flying, but it does require the development of a certain amount of ability to recognise a visual picture and in particular reasonably small differences in pitch angles.
I'm not really interested in arguing the point, but more in exploring what (to me at least) is an interesting paradox, probably partly explained by retinal depth cues and disparity, whereas there is no motion parallax as the pax can't see through the front window, so reducing the ability tof the brain to make inferences from the relative motion of objects, e.g. the threshold, or buildings.
Again, to be clear, motion parallax would not help to gauge airspeed, but it might provide a coarse sense of 'faster' or 'slower' is one was used to the environment.
(Of course one needs to remember that we are all unique, so my perceptions may be different to other peoples and perceptions are not reality.)
Get it clear everybody, you CANNOT judge speed or rate of descent from the cabin.
My point is that I cannot judge groundspeed at all, I get no sense of an approach being faster or slower, even though there must be quite a difference in aircraft types, weight, wind etc. All approaches to landing tend to be perceived as being the same by my senses.
I can't judge RoD either, in terms of 000 of feet per minute, but nearer to the ground (say 5-6,000 feet or less, with a clear horizon) due to the deck angle and the rate the scenery is growing, I find that I get a sense of normal (again, probably varies quite a lot in actuality) or unusual, e.g. LCY feels (or should I say more correctly looks) very different to LHR.
PPL training/VMC flying is nowhere near the standard of professional training or flying, but it does require the development of a certain amount of ability to recognise a visual picture and in particular reasonably small differences in pitch angles.
I'm not really interested in arguing the point, but more in exploring what (to me at least) is an interesting paradox, probably partly explained by retinal depth cues and disparity, whereas there is no motion parallax as the pax can't see through the front window, so reducing the ability tof the brain to make inferences from the relative motion of objects, e.g. the threshold, or buildings.
Again, to be clear, motion parallax would not help to gauge airspeed, but it might provide a coarse sense of 'faster' or 'slower' is one was used to the environment.
(Of course one needs to remember that we are all unique, so my perceptions may be different to other peoples and perceptions are not reality.)
Last edited by Final 3 Greens; 5th Feb 2009 at 11:53. Reason: Added last sentence
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"Like many of my colleagues, I am happy to have visitors to the flightdeck and welcome questions or constructive suggestions from passengers. Without them I wouldn't have a job for very long. Likewise, I'm happy to spend time on this forum enlightening pax and enthusiasts about what goes on behind the flightdeck door"
I would like to add to this and say thanks to pilots and crew for taking time to do this. Some of you may have seem some posts of mine with questions about "what happens if" and "strange Noises" but i have to say im not as nervous about flying as much i was and thats all becuase my questions were answered on this Forum! So Cheers!
Maybe more people should use this forum to ask sensible questions then there wouldnt be as many nervous passengers maybe?
Next 747 flight in March to San Fran hopefully! Looking forward to it!
As for hard landings on 737 aircraft, I was Flying with BMI Baby few weeks ago to Prague and thought the Landings were fine! Infact thought they were lighter and softer than the 747 which is the aircraft i spend most of my time on!
Thanks again!
"Like many of my colleagues, I am happy to have visitors to the flightdeck and welcome questions or constructive suggestions from passengers. Without them I wouldn't have a job for very long. Likewise, I'm happy to spend time on this forum enlightening pax and enthusiasts about what goes on behind the flightdeck door"
I would like to add to this and say thanks to pilots and crew for taking time to do this. Some of you may have seem some posts of mine with questions about "what happens if" and "strange Noises" but i have to say im not as nervous about flying as much i was and thats all becuase my questions were answered on this Forum! So Cheers!
Maybe more people should use this forum to ask sensible questions then there wouldnt be as many nervous passengers maybe?
Next 747 flight in March to San Fran hopefully! Looking forward to it!
As for hard landings on 737 aircraft, I was Flying with BMI Baby few weeks ago to Prague and thought the Landings were fine! Infact thought they were lighter and softer than the 747 which is the aircraft i spend most of my time on!
Thanks again!
Thread Starter
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First of all, I would like to offer my deepest thanks and gratitude to all of you who have responded to my original question.
I am very grateful and fortunate to have multiple professional pilots take the time and answer my questions.
Secondly, I now think I have the answer to my question:
1. The landing I experienced, was firmer than usual - but still within the normal operating requirements. Albeit, slightly unpleasant.
2. Landings which float down a runway are both unsafe and not recommended for an arrival.
3. Touching down in the right spot of the runway - is paramount.
4. Ryanair are very good airline, and I have had very good experiences with them, they have brought me, my siblings, and family and friends - all around Europe safely.
I know that the next time I am on a landing plane - I am safe, regardless of the touchdown.
I know that landings won't be completely silent nor feather soft.
However, some landings are soft, but safe! I know I have experienced these.
Once again, thank you for answering my questions and I would like to apologize to anyone I have offended.
I would be very grateful perhaps, if the discussion can be moved onto the landing gear itself?
I just have these questions:
1. How are they tested?
2. What can they take?
3. How long they last for and how often parts need changing?
Once again, thank you for you're continued help.
Best Regards,
Nikolai
I am very grateful and fortunate to have multiple professional pilots take the time and answer my questions.
Secondly, I now think I have the answer to my question:
1. The landing I experienced, was firmer than usual - but still within the normal operating requirements. Albeit, slightly unpleasant.
2. Landings which float down a runway are both unsafe and not recommended for an arrival.
3. Touching down in the right spot of the runway - is paramount.
4. Ryanair are very good airline, and I have had very good experiences with them, they have brought me, my siblings, and family and friends - all around Europe safely.
I know that the next time I am on a landing plane - I am safe, regardless of the touchdown.
I know that landings won't be completely silent nor feather soft.
However, some landings are soft, but safe! I know I have experienced these.
Once again, thank you for answering my questions and I would like to apologize to anyone I have offended.
I would be very grateful perhaps, if the discussion can be moved onto the landing gear itself?
I just have these questions:
1. How are they tested?
2. What can they take?
3. How long they last for and how often parts need changing?
Once again, thank you for you're continued help.
Best Regards,
Nikolai
If you Google "Landing Gear Testing", I promise that you will be able to spend hours and hours reading all about the subject. From military, through commercial to light aircraft. Every detail....promise..
FX Guru
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Re testing - my dad was an erk in the RAF in Asia in WW2.
The erks did their jobs very carefully as the pilots always insisted that they come up with them on the first test flight after repairs. In that way, if anything went wrong, at least the erks copped it as well.
Rather nifty move by the Nigels I've always thought!
The erks did their jobs very carefully as the pilots always insisted that they come up with them on the first test flight after repairs. In that way, if anything went wrong, at least the erks copped it as well.
Rather nifty move by the Nigels I've always thought!
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Years ago I saw a video of Boeing testing the 747, specifically its no flare landing capability. From the far end of the runway a camera filmed a 747 arriving at some truly scary descent rate - God knows how many feet per minute. On 'touchdown' (more like impact) the wings flexed, the engines shook on their pylons, and the aircraft looked like it had enough inertia to dig a big hole in the runway. But the gear held together. Mr. Boeing certainly builds 'em tough.
One of our engineers told me recently that what they regarded as a hard landing would to me feel like a crash. I believed him.
One of our engineers told me recently that what they regarded as a hard landing would to me feel like a crash. I believed him.
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Interesting! But wouldn't landing with such force, lets say in an emergency or just a hard landing - send the landing gear back inside the plane? And this could cause structural damage? Is this possible?
Can the forces damage the fuselage? Or is this not possible?
Once again, thank you very much for you're time.
Nikolai.
P.S
After watching some Youtube videos of other airlines landing the Boeing 737-800 NG with winglets - the firm part is normal! I would put this in the FAQ guide. Perhaps a few links of what is generally normal?
Can the forces damage the fuselage? Or is this not possible?
Once again, thank you very much for you're time.
Nikolai.
P.S
After watching some Youtube videos of other airlines landing the Boeing 737-800 NG with winglets - the firm part is normal! I would put this in the FAQ guide. Perhaps a few links of what is generally normal?
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Nothing is indestructible, and ultimately any component will fail, given enough force. Generally, the landing gear is designed to fail before the wings or fuselage, so that structural integrity is preserved as far as possible during a forced or crash landing. (Witness the BA777 at Heathrow - a severely damaged aircraft, but still in one piece).
If, by "send the landing gear back inside the plane", you mean "will it retract?" the answer is no. The gear is locked down both mechanically and hydraulically, and a hard landing would not cause it to retract.
If, by "send the landing gear back inside the plane", you mean "will it retract?" the answer is no. The gear is locked down both mechanically and hydraulically, and a hard landing would not cause it to retract.
