Hey everyone

 

I have been flying the a320 family for a while now, and have managed to learn its systems and characteritsics, also kinda smooth landings. But in the 738 my landings are so hard, no matter what I do. I flare 30ft agl just like in the airbus, but the aircraft behaves much differently.

Question one would be: are the Vref speeds set automatically by the aircraft? ( I mean with flaps 30 I always get around 150kts(+5kts wind correction or even more) and this seems a lot)

Question two would be: when do I stop trimming? So basically when Im established and disengage CMD, do I just input by force, and not trim? ( In the bus it stops the autotrim in LAND mode (400ft agl))

 

So yeah, I think this could be the reason why the aircraft behaves so weird when flaring, because I word not allowed up the trim of it + high approach speed.

But I only have about 80hrs in flight simming, so if someone knows better or even the answer to my question, I would greatly appreciate that.

 

Cheers, clear skies!

 

 

2 hours ago, Martin010 said:

Hey everyone

 

I have been flying the a320 family for a while now, and have managed to learn its systems and characteritsics, also kinda smooth landings. But in the 738 my landings are so hard, no matter what I do. I flare 30ft agl just like in the airbus, but the aircraft behaves much differently.

Question one would be: are the Vref speeds set automatically by the aircraft? ( I mean with flaps 30 I always get around 150kts(+5kts wind correction or even more) and this seems a lot)

Question two would be: when do I stop trimming? So basically when Im established and disengage CMD, do I just input by force, and not trim? ( In the bus it stops the autotrim in LAND mode (400ft agl))

 

So yeah, I think this could be the reason why the aircraft behaves so weird when flaring, because I word not allowed up the trim of it + high approach speed.

But I only have about 80hrs in flight simming, so if someone knows better or even the answer to my question, I would greatly appreciate that.

 

Cheers, clear skies!

 

 

Yes. The Airbus and Boeing are two different airplanes that behave differently. For example, the Airbus approach speeds differ significantly from the Boeing's. For example, a B748 at 300 T for landing will give you a Vref of 165, while the A380 will give you a Vref of 145.

 

Autotrim is different between the aircraft. On the Airbus, as you mentioned, at 400 feet, the auto trim disengages, and the aircraft transitions to direct law or alternate law (based on the flight control system status). This allows the pilot full manual control over pitch to make precise adjustments.

 

On the Boeing, you can trim anytime, but they recommend not to do so during flare.

 

On the other note, similar to the two aircraft, in normal smooth WX conditions, when the AP is disengaged, the airplane is in trim and will require very little to no corrections during the approach down to the runway. Considering that we have different wings, flaps, and speeds,  I would recommend doing a few autolands for you to see the notions and differences in purpose and nail it down. The funny part is that no matter how good we are in real life, 2 out of 10 will be "different." Remember, practice is the key, and we learn something new every flight regardless of what we think we know.

On 3/13/2025 at 10:11 PM, LRBS said:

 

when the AP is disengaged, the airplane is in trim and will require very little to no corrections during the approach down to the runway. 

Thanks a lot

So when I disengage and make those adjustments, should I not trim those at all? Or should I follow the airbus system, like I trim until 400ft?

1 hour ago, Martin010 said:

Thanks a lot

So when I disengage and make those adjustments, should I not trim those at all? Or should I follow the airbus system, like I trim until 400ft?

You are welcome. In real life, we trim as necessary but stop before flare. If you used to that 400 FT, do it that way.

I know no one is even going to read this, but Im so excited for it I dont care! Even if one person can get some info from this its a win-win. Ive made the first acceptable landing with the -800!

Ive used manual thrust, which I thought was going to be harder to maintain speed with, but it was actually kinda easy, I only had to adjust around 7% N1. I was stabilised the whole approach!

From CMD disconnect I didnt trim as it wasnt neccessary, I only made very little adjustments. I was a tiny bit above the glideslope but still within the touchdown zone. I actually think this happened because Im used to the airbuses autotrim.

So yeah, the landing and the flare was still a bit rough, but much better than before, practice will make perfect! And this was the first flight since I wrote here, I cleared the things in my head, I was ahead of the plane, and it turns out that if you dont panic and rush it, it is kinda easy!

If you are reading this and having the same problems that I had, dont give up! If I could (partially:D) do it then anyone can do it!

 

 

Edited March 20, 20251 yr by Martin010

I flew all the "Classic and Jurassic" 737's  for a number of years.   One salient point is if you are stable on approach (GS/LOC) and disconnect the A/P you should need no trim change.   Often if in trim and stable conditions one can fly a nuts on approach by not touching anything.  Self induced turbulence can be an issue.    Non FBW Boeings have considerable pitch change with thrust adjustment. Actually a good thing!    So A/P off, A/T off is a suggestion. You will find the plane speed stable.  Since your desk throttles do not move like the real ones, note the N1 and match when disconnecting. If your plane displays the sim thrust lever position match that way.   At about 30' with say about an 800 fpm descent rate a very minor pitch change is necessary , 2 deg or so and thrust smoothly brought to idle. Look at the far end of the runway and ease off a little if she doesn't kiss the ground.