Hi all

What do you think is a good landing? Is it 100fpm touchdown or perhaps 50 fpm for a smooth landing? Is it different for a heavy 747 compared to a 737 or a CJ4?

 

What do you think?

For a Boeing I came across this document which has the following speeds:

• 60-120 fpm is normal.
• >240 fpm is considered a hard landing
• >360 fpm:  risking damage if aircraft is overweight.
• >600 fpm:  please don't.

I'd like to know as well what the numbers would be for light aircraft.

I must say that since I started using the Neofly addon my landings have become considerably softer (hard landings damages your cargo). A good yoke also helped a lot to stabilise my approaches.

G-force is more important than the fpm value. There's a free app called Gees which records a bunch of data whenever you land, it's very good. I try to aim for no more than 1.2G in whatever aircraft I'm flying.

Somewhere I remember reading that Airbus' A320 autoland is supposed to give a descent rate in the flare of ~150fpm to prevent aquaplaning at touchdown on a contaminated runway. Literally, smash through the surface water.

when you hear a bang from the speakers and your view shakes in the sim and you think  oooppss..  then it was too hard.  If the screen goes black and says you have crashed.. it was way to hard..  if you don't actually realise you have wheels on the ground but you do.. it was probably a bit to soft.  If you get surrounded by a cloud of smoke, then you forgot to lower your undercarriage, but yes, even with damage on it's possible to land with wheels up in MSFS2020.

If the VASI is showing half white, half red  you are fine on approach,  if all red, you are too low..  if some of the VASI are green, you are very low and looking at them through the grass.

in reality 100-120 fpm is pretty solid  as mentioned above..  a little more towards the 120 if there is rain or snow on the runway.

Graham

The slope of the runway also matters.

Yes 120 fpm downwards is usually OK though it might bounce you in a warrior ( that is 2 feet per second after all)  but it will actually smack quite hard if the runway has a 20 degree up hill slope 😄

An airliner such as a typical Boeing can actually handle up to about 600 fpm before it will break the landing gear, but that would be a regarded as a 'hard' landing and would usually require the crew to report it and get an engineer to give the aeroplane a once over. When over the maximum landing weight, the maximum touchdown rate would be limited to nothing over around 350 fpm. Typically however, pilots of airliners would aim for nothing above 250 fpm on a normal landing.

Contrary to popular belief however, airliners (and a lot of GA aeroplanes too) are actually meant to be flown fairly positively onto the deck rather than floated onto the surface to kiss it really gently; this is because if you come down too gently, the tires will skip about on the surface and get more wear on them than if they come down into contact fairly positively so they can then immediately start rolling along the surface and utilising the brakes with a decent amount of grip instead of skidding. Not only this, airliners typically have a weight on the wheels sensor which triggers a few things that you want ASAP upon touchdown. They do this by detecting that the oleos on the landing gear are compressed. On an Airbus A320 for example, this weight on the wheels sensor triggers the spoilers deploying (providing they are armed) and it also halves the aileron input ratio so that if you are crabbing a landing with the wing down, when you touchdown, it prevents excessive opposite control inputs on the aileron from perhaps causing an engine pod strike by inadvertently inputting too much aileron deflection. 

Aircraft carrier jets and props are a bit different though. They are designed to come down really pretty hard because what that does is absorb a lot of the energy from flight as a downward impact rather than the aeroplane retaining a lot of forward motion. This makes the aeroplane easier to slow down with the arrestor wires. So it's not uncommon for a carrier jet fighter or similar to come down at 700 fpm because the thing is designed to take that kind of thing, although they might have to jettison external stores to be able to do this. You won't find most carrier landings being less than maybe 450 fpm, although what the oleos on most carrier aeroplanes do have, is a controlled release valve on them which slowly lets the compression off to prevent the aeroplane from bouncing back into the air.

Edited August 17, 20214 yr by Chock

Too softer a landing in a 737 can cause bad landing gear oscillation, there's a youtube video somewhere demonstrating it.

1G is a pretty good landing. 1.1G is the best for the plane and the overrun foam at the other end of the runway.

50 minutes ago, Bunchy said:

Too softer a landing in a 737 can cause bad landing gear oscillation, there's a youtube video somewhere demonstrating it.

Ryanair like this post.

1 hour ago, Moria15 said:

If the VASI is showing half white, half red  you are fine on approach,  if all red, you are too low..  if some of the VASI are green, you are very low and looking at them through the grass.

White over white = you'll be flying all night.

Red over red = You'll bump your head.

😉 

3 hours ago, clayton4115 said:

Hi all

What do you think is a good landing? Is it 100fpm touchdown or perhaps 50 fpm for a smooth landing? Is it different for a heavy 747 compared to a 737 or a CJ4?

 

What do you think?

For the 747 and 380 the autopilot will target a 50 FT/MIN touchdown in ideal conditions. Most of the time autolandings are very smooth, also there are situations where a malfunction will occur as to no flare or just due to whatever reasons (drastic wx changes) and simply it can't react fast enough.

Manual landings using proper technics "could" lead to smooth landings between 50 / 100 FT/MIN, actually, there are guidelines (for the 747 x 380) where if the autopilot exceeds -300 FT/MIN at touchdown and entry to be made in the logbook.

 

For a 747 x 380 a normal rate of descending before flare is somewhere between -600 to -800 FT/MIN based on many factors, the issue is not the landing gear not being able to take the load, it is the FLAPS, if the ROD at touchdown was in excess of -700 FT/MIN (hard landing)  maintenance has to do an inspection.

 

Regarding overweight landings, it's all about Vref speeds that will lead to a higher ROD to be on profile and anticipation of flaring, actually, there is no max touchdown rate as of anything over around -350 FT/MIN.

 

On a carrier, we used to touchdown between -600 to -1000 F/MIN (no flare) and actually adding max power before catching the wire.

 

For the small ones, there are so many things that can go wrong and beyond our control and makes it interesting. 

3 hours ago, lambourne said:

G-force is more important than the fpm value. There's a free app called Gees which records a bunch of data whenever you land, it's very good. I try to aim for no more than 1.2G in whatever aircraft I'm flying.

Somewhere I remember reading that Airbus' A320 autoland is supposed to give a descent rate in the flare of ~150fpm to prevent aquaplaning at touchdown on a contaminated runway. Literally, smash through the surface water.

This. For most jurisdictions, the vertical speed is considered a secondary parametre only.

4 hours ago, Moria15 said:

if some of the VASI are green, you are very low and looking at them through the grass

😆

3 hours ago, 109Sqn said:

if some of the VASI are green, you are very low and looking at them through the grass

If they look really far away, you are trying to land at Paris Charles De Gaulle, but looking at Paris Orly's runway. 🤣

Edited August 17, 20214 yr by Chock

what would be a good landing in fpm for a CJ4?