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Pudelhund
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737 MAX - Pilots complain of fast landings?

Mon Feb 25, 2019 8:19 pm

My friend said the following about the 737 MAX, but I cannot find any material to support these assertions. Is there any truth to them?

“The pilots complain about high landing speed... Because it's longer than most 737s. It's better than the -900 because the max sits higher. But they land at the same speed as a 757 with Half the breaking power... [they have] half the wheels, brakes tend to get too hot.”
 
VSMUT
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Re: 737 MAX - Pilots complain of fast landings?

Mon Feb 25, 2019 8:45 pm

Well it has the same wings, but weighs somewhere between 4 and 8 tons more, so you have to compensate that with more speed. That is basic knowledge.

Same with the wheels and brakes.

The 737MAX is a massively compromised design. Most sensible people predicted these issues long before the first metal was cut.
 
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AirKevin
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Re: 737 MAX - Pilots complain of fast landings?

Mon Feb 25, 2019 11:29 pm

Pudelhund wrote:
“The pilots complain about high landing speed... Because it's longer than most 737s. It's better than the -900 because the max sits higher. But they land at the same speed as a 757 with Half the breaking power... [they have] half the wheels, brakes tend to get too hot.”

I don't know about landing at the same speed as a 757. I thought the 757 could go as slow as 112 knots on approach.
 
Max Q
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Re: 737 MAX - Pilots complain of fast landings?

Tue Feb 26, 2019 5:34 am

AirKevin wrote:
Pudelhund wrote:
“The pilots complain about high landing speed... Because it's longer than most 737s. It's better than the -900 because the max sits higher. But they land at the same speed as a 757 with Half the breaking power... [they have] half the wheels, brakes tend to get too hot.”

I don't know about landing at the same speed as a 757. I thought the 757 could go as slow as 112 knots on approach.




The 757 does have a fairly slow approach speed, especially at lighter weights



The reason for the longer body 737’s high approach (and take off) speeds is to keep the pitch attitude from being too high and risk a tail strike


The 757-300 and 767-400 with their longer fuselages use higher speeds for the same reason, on the other hand they have excellent brakes and stop very well
 
VSMUT
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Re: 737 MAX - Pilots complain of fast landings?

Tue Feb 26, 2019 7:46 am

Max Q wrote:
The 757-300 and 767-400 with their longer fuselages use higher speeds for the same reason, on the other hand they have excellent brakes and stop very well


They have 4-wheel bogies. They can get away with weaker individual brakes, but still have better overall effect.
 
stratclub
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Re: 737 MAX - Pilots complain of fast landings?

Tue Feb 26, 2019 11:25 am

It must not be a deal breaker, because the FAA did certify it. You have to remember that brake technology has come a long way in the last 30 years or so.
 
WIederling
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Re: 737 MAX - Pilots complain of fast landings?

Tue Feb 26, 2019 6:36 pm

stratclub wrote:
It must not be a deal breaker, because the FAA did certify it.


That could turn around and bite. MCAS, 787 batteries, ..
 
SteelChair
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Re: 737 MAX - Pilots complain of fast landings?

Tue Feb 26, 2019 7:13 pm

The FAA certified the MD-11 also, and the GTF for ETOPS. Just because the FAA certified it.....oh well.

I agree that the 739 and 10 are seriously compromised designs. Full flaps decreases tail clearance and one notch less than full increases landing distance.
 
stratclub
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Re: 737 MAX - Pilots complain of fast landings?

Tue Feb 26, 2019 7:14 pm

I think more so the fact that the 737 is a victim of it's own success and because of that is pretty long in the tooth. The MCAS fiasco certainly is proof of that. It did surprise when Boeing stop production on the 757 instead of letting the 737 fade away into history. Still, once the MCAS fiasco is properly understood and trained for by flight crews the MAX will be a great plane.

What's really sad is that if the Lion Air crew would have understood MCAS, all they would have had to do is put the flaps back to at least flaps 1 and the aircraft could have stopped automatic MCAS down trimming and they would have completed their go around and landed safely. Damn shame............
 
Redbellyguppy
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Re: 737 MAX - Pilots complain of fast landings?

Tue Feb 26, 2019 8:31 pm

Those brakes work surprisingly well. I make the reverse at 24R LAX without particularly heavy braking.
 
FriscoHeavy
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Re: 737 MAX - Pilots complain of fast landings?

Tue Feb 26, 2019 11:59 pm

Pudelhund wrote:
My friend said the following about the 737 MAX, but I cannot find any material to support these assertions. Is there any truth to them?

“The pilots complain about high landing speed... Because it's longer than most 737s. It's better than the -900 because the max sits higher. But they land at the same speed as a 757 with Half the breaking power... [they have] half the wheels, brakes tend to get too hot.”



Contrary to another poster, it's not a compromised design. They are being silly.

As to your statement that you relayed on, are you speaking about the 737-8MAX or -9MAX? The 737-800 and -8MAX are virtually the same size. Yes, the MAX is a bit heavier, but it also sits higher off the ground and has a larger wing, so if anything, it should have better performance.

Also, United is now able to fly the -9MAX to OGG, whereas the -900ER had performance issues. Again, this bodes well for the -9MAX and shows that it actually has better performance than it's NG predecessor.

The -10MAX will be interesting to see, but I believe it will perform better than most are willing to give it credit for.
 
FlyHossD
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Re: 737 MAX - Pilots complain of fast landings?

Wed Feb 27, 2019 4:54 am

Pudelhund wrote:
My friend said the following about the 737 MAX, but I cannot find any material to support these assertions. Is there any truth to them?

“The pilots complain about high landing speed... Because it's longer than most 737s. It's better than the -900 because the max sits higher. But they land at the same speed as a 757 with Half the breaking power... [they have] half the wheels, brakes tend to get too hot.”


IIRC, Boeing guaranteed that the -9Max's approach speeds would not be more than 1 knot greater than the -900ER. So anyone who has flown the -900ER should be comfortable in the -9Max, eh? So maybe your friend is pulling your leg.
 
Natflyer
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Re: 737 MAX - Pilots complain of fast landings?

Sat Mar 02, 2019 9:23 am

The 737MAX is the fastest airplane in our fleet.
From Outer Marker to the runway.
 
TTailedTiger
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Re: 737 MAX - Pilots complain of fast landings?

Sat Mar 02, 2019 9:20 pm

FriscoHeavy wrote:
Pudelhund wrote:
My friend said the following about the 737 MAX, but I cannot find any material to support these assertions. Is there any truth to them?

“The pilots complain about high landing speed... Because it's longer than most 737s. It's better than the -900 because the max sits higher. But they land at the same speed as a 757 with Half the breaking power... [they have] half the wheels, brakes tend to get too hot.”



Contrary to another poster, it's not a compromised design. They are being silly.

As to your statement that you relayed on, are you speaking about the 737-8MAX or -9MAX? The 737-800 and -8MAX are virtually the same size. Yes, the MAX is a bit heavier, but it also sits higher off the ground and has a larger wing, so if anything, it should have better performance.

Also, United is now able to fly the -9MAX to OGG, whereas the -900ER had performance issues. Again, this bodes well for the -9MAX and shows that it actually has better performance than it's NG predecessor.

The -10MAX will be interesting to see, but I believe it will perform better than most are willing to give it credit for.


Thank you for a informative and rational post. :bigthumbsup:

Some people really need to tone down the dramatics.
 
747Whale
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Re: 737 MAX - Pilots complain of fast landings?

Sat Mar 02, 2019 9:48 pm

Pudelhund wrote:
My friend said the following about the 737 MAX, but I cannot find any material to support these assertions. Is there any truth to them?

“The pilots complain about high landing speed... Because it's longer than most 737s. It's better than the -900 because the max sits higher. But they land at the same speed as a 757 with Half the breaking power... [they have] half the wheels, brakes tend to get too hot.”


Maybe your friend has never flown anything bigger or heavier, but if pilots are whining about the approach speed it's likely that the came from a regional and have no basis for comparison.

The speed really doesn't matter. Performance charts are available to address the landing data, and if the landing data is satisfied, then that's all that really need be known. An airplane flies an approach at 180 knot about the same as 130; the difference is a little higher descent rate, and different numbers. I see speeds high and low depending on weight, and all I care about is that the numbers are correct for the weight and conditions, and then I fly the numbers.

Brakes are not inadequate. Brakes are brakes, and landing performance data exists to reflect what can be expected from those brakes for given field conditions and weight. Where reverse is used on landing, reverse reduces the amount of brake required for a given rate of acceleration, and the numbers remain the same.

It's not as if crews are pressing the boundaries of safety thanks to excessive landing speeds; the airplane is landed at whatever speed is appropriate for the weight and conditions; the actual number is irrelevant so long as it's the right number. Warm brakes are a fact of life, largely reduced for those using carbon brakes.
 
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GEUltraFan9XGTF
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Re: 737 MAX - Pilots complain of fast landings?

Sat Mar 02, 2019 10:56 pm

An entire thread based on vague hearsay?
 
LH707330
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Re: 737 MAX - Pilots complain of fast landings?

Sat Mar 02, 2019 11:58 pm

GEUltraFan9XGTF wrote:
An entire thread based on vague hearsay?

Is that unusual here? :P
 
FlyHossD
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Re: 737 MAX - Pilots complain of fast landings?

Sun Mar 03, 2019 12:21 am

LH707330 wrote:
GEUltraFan9XGTF wrote:
An entire thread based on vague hearsay?

Is that unusual here? :P


Well played - thank you. But to be fair, this board isn't the only one where facts aren't necessary. Or common.
 
BoeingGuy
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Re: 737 MAX - Pilots complain of fast landings?

Sun Mar 03, 2019 1:20 am

FlyHossD wrote:
LH707330 wrote:
GEUltraFan9XGTF wrote:
An entire thread based on vague hearsay?

Is that unusual here? :P


Well played - thank you. But to be fair, this board isn't the only one where facts aren't necessary. Or common.


Actually the thread does have truth to it. I’ve heard this too. Supposedly UA complained about high 737 approach speeds at DEN, among others.

One of the main reason that the 737NG and 737 Max have higher landing speeds than the A32x is that it’s not recommended to fly the approach with the Autopilot off and Autothrottle on due to possible pitch/thrust coupling issues. If you hand fly the approach on a 737, you are supposed to also have the Autothrottle off.

When you land without the Autothrottle engaged you have to add a gust additive to your approach speed. That can quickly add as much as 10-15 knots.

AA ignores the recommendation and keeps the autothrottle engaged even when landing manually in their 737s with some procedural guidance how to do it. The A32x series does allow keeping Autothrust engaged when hand flying the approach, thus doesn’t need the wind additive.

Some potential solutions are being explored for the 737. I’ll leave it at that.
 
Max Q
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Re: 737 MAX - Pilots complain of fast landings?

Sun Mar 03, 2019 3:06 pm

Personally I’ve never understood the rationale for pilots complaining about higher approach speeds


Given the choice (within reason) I’ve always preferred the handling characteristics of a heavier aircraft and / or higher landing speed


In gusty, crosswind conditions a faster speed on final will have you ‘blown around’ far less, you ‘point it and it goes there’


You’ll have a higher descent rate and need to plan the flare earlier but that’s not an issue


I’d rather fly a fast, heavy 767 at maximum landing weight in any conditions rather than a light 757 at 120 knots that gets blown around like a kite


Never flown a 737 but that’s been true across all other types I’ve flown
 
bgm
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Re: 737 MAX - Pilots complain of fast landings?

Sun Mar 03, 2019 3:53 pm

FriscoHeavy wrote:
Contrary to another poster, it's not a compromised design. They are being silly.


Really? It's not a compromised design? How do you explain the tiny stubby landing gear (originally designed for JT8D clearance)? Look at the deformed shape of the CFM56/Leap-1B to make it fit on the wings. Or the 737 MAX 10 with the telescopic landing gear? Boeing most definitely had to make compromises to make everything fit. Look at the Leap 1A vs 1B to see the normal/deformed difference between the engines.

FriscoHeavy wrote:
As to your statement that you relayed on, are you speaking about the 737-8MAX or -9MAX? The 737-800 and -8MAX are virtually the same size. Yes, the MAX is a bit heavier, but it also sits higher off the ground and has a larger wing, so if anything, it should have better performance.


I didn't realize that Boeing had increased the wing size on the MAX? Or do you mean new winglets have increased the overall wing area a little?

Landing with a higher approach speed isn't necessarily dangerous in itself, but the airplane will be landing with much more energy that needs to be dissipated. You're far more likely to bounce/float/balloon and require consistently heavier braking/reverse thrust.

FriscoHeavy wrote:
Also, United is now able to fly the -9MAX to OGG, whereas the -900ER had performance issues. Again, this bodes well for the -9MAX and shows that it actually has better performance than it's NG predecessor.


Well, given that the Leap has ~15% improved efficiency over the CFM56, it would be a bit damning if the performance decreased. ;)
FriscoHeavy wrote:
The -10MAX will be interesting to see, but I believe it will perform better than most are willing to give it credit for.


What is your belief based on?
 
arcticcruiser
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Re: 737 MAX - Pilots complain of fast landings?

Sun Mar 03, 2019 9:09 pm

Pudelhund wrote:
My friend said the following about the 737 MAX, but I cannot find any material to support these assertions. Is there any truth to them?

“The pilots complain about high landing speed... Because it's longer than most 737s. It's better than the -900 because the max sits higher. But they land at the same speed as a 757 with Half the breaking power... [they have] half the wheels, brakes tend to get too hot.”


The MAXes land faster than a 757, even a -300. Here are the Vref numbers at Max Landing Weight (at sea level):

B757-200 (95t MLW) 137 kts
B757-300 (101t MLW) 143 kts
B767-300 (145t MLW) 145 kts
B737-8 (69t MLW) 149 kts Flaps 30 144 kts Flaps 40
B737-9 (74t MLW) ~153 kts Flaps 30 ~149 kts Flaps 40 This is probably accurate to +/- 1 kt.

Flaps 40 have rarely been used on the 737 Jurassic/Classic/NG except into short runways. Question is whether we will be increase in the use of Flaps 40 on the Maxes.
 
VSMUT
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Re: 737 MAX - Pilots complain of fast landings?

Sun Mar 03, 2019 9:59 pm

FlyHossD wrote:

IIRC, Boeing guaranteed that the -9Max's approach speeds would not be more than 1 knot greater than the -900ER. So anyone who has flown the -900ER should be comfortable in the -9Max, eh? So maybe your friend is pulling your leg.


At the same weight, sure. But an empty MAX is 4 tons heavier than a Next Generation.
 
FlyHossD
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Re: 737 MAX - Pilots complain of fast landings?

Sun Mar 03, 2019 11:46 pm

BoeingGuy wrote:
FlyHossD wrote:
LH707330 wrote:
Is that unusual here? :P


Well played - thank you. But to be fair, this board isn't the only one where facts aren't necessary. Or common.


Actually the thread does have truth to it. I’ve heard this too. Supposedly UA complained about high 737 approach speeds at DEN, among others.

One of the main reason that the 737NG and 737 Max have higher landing speeds than the A32x is that it’s not recommended to fly the approach with the Autopilot off and Autothrottle on due to possible pitch/thrust coupling issues. If you hand fly the approach on a 737, you are supposed to also have the Autothrottle off.

When you land without the Autothrottle engaged you have to add a gust additive to your approach speed. That can quickly add as much as 10-15 knots.

AA ignores the recommendation and keeps the autothrottle engaged even when landing manually in their 737s with some procedural guidance how to do it. The A32x series does allow keeping Autothrust engaged when hand flying the approach, thus doesn’t need the wind additive.

Some potential solutions are being explored for the 737. I’ll leave it at that.


Your info about UA 737NGs is not correct. Yes, I flew them at CO, then UA.
 
FlyHossD
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Re: 737 MAX - Pilots complain of fast landings?

Sun Mar 03, 2019 11:51 pm

arcticcruiser wrote:
Pudelhund wrote:
My friend said the following about the 737 MAX, but I cannot find any material to support these assertions. Is there any truth to them?

“The pilots complain about high landing speed... Because it's longer than most 737s. It's better than the -900 because the max sits higher. But they land at the same speed as a 757 with Half the breaking power... [they have] half the wheels, brakes tend to get too hot.”


The MAXes land faster than a 757, even a -300. Here are the Vref numbers at Max Landing Weight (at sea level):

B757-200 (95t MLW) 137 kts
B757-300 (101t MLW) 143 kts
B767-300 (145t MLW) 145 kts
B737-8 (69t MLW) 149 kts Flaps 30 144 kts Flaps 40
B737-9 (74t MLW) ~153 kts Flaps 30 ~149 kts Flaps 40 This is probably accurate to +/- 1 kt.

Flaps 40 have rarely been used on the 737 Jurassic/Classic/NG except into short runways. Question is whether we will be increase in the use of Flaps 40 on the Maxes.


More disinformation. I regularly used flaps 40 on CO, then UA, 737NGs and not just for short runways. At times, it was prudent to use flaps 40 in order to save taxi time (i.e., when the gate was behind you).

Also, it's my understanding from colleagues still at UA that flaps 40 is the standard flap setting for landing on the -9Max aircraft. That is, some pilots didn't like F40 on the NGs because of how that affected the roll spoilers (afraid of roll PIO). However, the spoilers on the 737Max aircraft are fly-by-wire and don't have the same roll issue.
 
FlyHossD
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Re: 737 MAX - Pilots complain of fast landings?

Sun Mar 03, 2019 11:52 pm

VSMUT wrote:
FlyHossD wrote:

IIRC, Boeing guaranteed that the -9Max's approach speeds would not be more than 1 knot greater than the -900ER. So anyone who has flown the -900ER should be comfortable in the -9Max, eh? So maybe your friend is pulling your leg.


At the same weight, sure. But an empty MAX is 4 tons heavier than a Next Generation.


An interesting point. I'll ask for a direct comparison although even that isn't precise since the Max aircraft are heavier empty.
 
BoeingGuy
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Re: 737 MAX - Pilots complain of fast landings?

Mon Mar 04, 2019 1:01 am

FlyHossD wrote:
BoeingGuy wrote:
FlyHossD wrote:

Well played - thank you. But to be fair, this board isn't the only one where facts aren't necessary. Or common.


Actually the thread does have truth to it. I’ve heard this too. Supposedly UA complained about high 737 approach speeds at DEN, among others.

One of the main reason that the 737NG and 737 Max have higher landing speeds than the A32x is that it’s not recommended to fly the approach with the Autopilot off and Autothrottle on due to possible pitch/thrust coupling issues. If you hand fly the approach on a 737, you are supposed to also have the Autothrottle off.

When you land without the Autothrottle engaged you have to add a gust additive to your approach speed. That can quickly add as much as 10-15 knots.

AA ignores the recommendation and keeps the autothrottle engaged even when landing manually in their 737s with some procedural guidance how to do it. The A32x series does allow keeping Autothrust engaged when hand flying the approach, thus doesn’t need the wind additive.

Some potential solutions are being explored for the 737. I’ll leave it at that.


Your info about UA 737NGs is not correct. Yes, I flew them at CO, then UA.


What is not correct? I’ve been directly involved with a project associated with this issue. ;) Please tell me what I’m not correct about.
 
FlyHossD
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Re: 737 MAX - Pilots complain of fast landings?

Mon Mar 04, 2019 3:25 am

BoeingGuy wrote:
FlyHossD wrote:
BoeingGuy wrote:

Actually the thread does have truth to it. I’ve heard this too. Supposedly UA complained about high 737 approach speeds at DEN, among others.

One of the main reason that the 737NG and 737 Max have higher landing speeds than the A32x is that it’s not recommended to fly the approach with the Autopilot off and Autothrottle on due to possible pitch/thrust coupling issues. If you hand fly the approach on a 737, you are supposed to also have the Autothrottle off.

When you land without the Autothrottle engaged you have to add a gust additive to your approach speed. That can quickly add as much as 10-15 knots.

AA ignores the recommendation and keeps the autothrottle engaged even when landing manually in their 737s with some procedural guidance how to do it. The A32x series does allow keeping Autothrust engaged when hand flying the approach, thus doesn’t need the wind additive.

Some potential solutions are being explored for the 737. I’ll leave it at that.


Your info about UA 737NGs is not correct. Yes, I flew them at CO, then UA.


What is not correct? I’ve been directly involved with a project associated with this issue. ;) Please tell me what I’m not correct about.


Yes, the 737NGs have high approach speeds, but that's true at any airport - not just DEN. And if you're referring to the difference in groundspeed due to the difference in true airspeed at higher elevations, again that's true at any higher altitude airport - not just DEN. It would be true at ABQ or MEX or SLC, too - would it not? Yet DL has 73Gs, 738s and 739s and where are the complaints there? Or at Alaska?

Further, the CO/UA FM didn't prevent hand-flown approaches with the auto-throttles engaged to the best of my recollection. Coincidentally, I did prefer to hand fly approaches with the auto-throttles on until reaching the landing flap setting; my log shows 15,000+ hours in 737s, the vast majority in the NGs.
 
BoeingGuy
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Re: 737 MAX - Pilots complain of fast landings?

Mon Mar 04, 2019 4:19 am

FlyHossD wrote:
BoeingGuy wrote:
FlyHossD wrote:

Your info about UA 737NGs is not correct. Yes, I flew them at CO, then UA.


What is not correct? I’ve been directly involved with a project associated with this issue. ;) Please tell me what I’m not correct about.


Yes, the 737NGs have high approach speeds, but that's true at any airport - not just DEN. And if you're referring to the difference in groundspeed due to the difference in true airspeed at higher elevations, again that's true at any higher altitude airport - not just DEN. It would be true at ABQ or MEX or SLC, too - would it not? Yet DL has 73Gs, 738s and 739s and where are the complaints there? Or at Alaska?

Further, the CO/UA FM didn't prevent hand-flown approaches with the auto-throttles engaged to the best of my recollection. Coincidentally, I did prefer to hand fly approaches with the auto-throttles on until reaching the landing flap setting; my log shows 15,000+ hours in 737s, the vast majority in the NGs.


I’m talking about leaving the Autothrottle engaged until touch down with the Autopilot off. The Boeing Flight Crew Training Manual and Flight Crew Operations Manual recommend against doing so for a couple of reasons that I can discuss in detail. One is thrust-pitch coupling. The other is that the Autothrottle will retard to IDLE only in certain pitch modes. There are some scenarios where it wouldn’t retard to IDLE such as a circling to approach if your Flight Director pitch mode is in ALT HLD.

As I clearly stated in my previous post, I’m not talking about difference in ground speed at a higher elevation airport. I was talking about the FACT that the 737 has a higher approach speed than the A32x series and some customers’ management have raised issue with it.

I’m glad you are happy with the airplane. That’s a good thing.
 
FlyHossD
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Re: 737 MAX - Pilots complain of fast landings?

Mon Mar 04, 2019 5:06 am

BoeingGuy wrote:

I’m talking about leaving the Autothrottle engaged until touch down with the Autopilot off. The Boeing Flight Crew Training Manual and Flight Crew Operations Manual recommend against doing so for a couple of reasons that I can discuss in detail. One is thrust-pitch coupling. The other is that the Autothrottle will retard to IDLE only in certain pitch modes. There are some scenarios where it wouldn’t retard to IDLE such as a circling to approach if your Flight Director pitch mode is in ALT HLD.

As I clearly stated in my previous post, I’m not talking about difference in ground speed at a higher elevation airport. I was talking about the FACT that the 737 has a higher approach speed than the A32x series and some customers’ management have raised issue with it.

I’m glad you are happy with the airplane. That’s a good thing.


In rereading your previous post, you did not distinguish between landing an auto-landing with the auto-throttles on or a manual landing with the auto-throttles on*. However, with the additional information contained in your last post, I now understand your intent.

Who at UA complained? Or more specifically, was it anyone with 737NG experience? Going into the merger, none of the pmUA Flight Ops management could truthfully claim any such experience, could they?

I've been retired for a few years now (finished on the 757/767), but I spent over 17 years on the 737s at CO then UA (including a few years as a Check Airman). Also, I'm in regular contact with colleagues at UA. From several prior conversations with them and from my direct personal experiences, I can confidently tell you that the premise of this thread is flawed. You shouldn't afford too much credence to someone who hasn't flown the airplane.

P.S. It's easy to override the auto-throttles, so if you were to land with the auto-throttles on, it's not a problem to retard thrust to idle. Indeed, you indicated that AA does something like that.

*"it’s not recommended to fly the approach with the Autopilot off and Autothrottle on due to possible pitch/thrust coupling issues"
 
Avgeek21
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Re: 737 MAX - Pilots complain of fast landings?

Mon Mar 04, 2019 6:47 am

Interesting. I'm a 737 Captain currently flying the -800, MAX 8 and 9. In my honest opinion I can tell you that the MAX is a lovely aircraft. There is a difference between the -800 and MAX 8. The MAX performance is staggering. In a like-for-like situation the MAX 8 will lift about 4 tonnes (metric) more under identical conditions vs the -800. Still the same old 737 grand design but the MAX is a joy to fly. It is noticeably precise and more stable than the -800. For the same Cost Index it flies about M0.01 faster too. It may look insignificant but that's nice. Is it quieter? Not really upfront. I've measure 1 Decibel dB less on the MAX so I'd say it's negligable. It the back it's a whole different story. So quiet it actually annoyes me at times when I can hear normal conversations a few rows behind. Nothing some headphones can't solve.

It does have some fast rotation speeds at heavy weights though. We (my operator) don't use balanced field takeoffs but at heavy weights, sea level and a nearly 4k runway you are looking at a Vr of around 160-165 kts.

Takeoff

Anyways I used our official Boeing OPT below for some accurate data at max takeoff weight (MTOW). All conditions are identical, just the model is different;
-800 - Vr 159
MAX 8 - Vr 161
MAX 9 - Vr 166. Interestingly the MAX 9 here is RTOW limited by about 1200kgs. It would need an additional 450 meters to be able to lift off at MTOW.

Landing

I used our official Boeing OPT below for some accurate data at max landing weight (MLW). All conditions are identical, just the model is different;
-800 - Vref30+ 5 = 152 - Stopping distance Autobrakes 2 (dry runway + no reversers) = 3283m
MAX 8. - Vref30+5 = 153 - Stopping distance Autobrakes 2 (dry runway + no reversers) = 3312m
MAX 9 - Vref30+5 = 154 - Stopping distance Autobrakes 2 (dry runway + no reversers) = 3401m

So yes, it's faster on approach the heavier you get and it uses a bit more runway. The MAX 9 is also a CAT-D aircraft vs a CAT-C for the -800/MAX 8 due to it's faster threshold speed.

I have zero issue stopping the 737. It brakes really well imho. (carbon brakes) I've landed on plenty of braking action poor runways on the -800. Not yet on the MAX.

With the 737 MAX you just have to think about energy management more because it just doesn't want to slow down in the air. It's very slippery. And you have to be carefull pulling the fly-by-wire spoilers. You are used to resistance on the handle with the NG but that's not there on the MAX so one tends to pull it too fast. No big deal.

I love the MAX. It may be an old design but it makes me smile every time I fly it. Especially when it spools up on takeoff.

P.S. My first post on A.net after lurking here daily for 10-15 years. So go easy... ;-)
 
VSMUT
Posts: 5497
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Re: 737 MAX - Pilots complain of fast landings?

Mon Mar 04, 2019 9:02 am

Max Q wrote:
Personally I’ve never understood the rationale for pilots complaining about higher approach speeds


We are talking 737s here, they regularly land on much smaller runways than your 767 does. They don't always have the luxury of big, wide 3 km runways. And as somebody else noted, the 737MAX lands as fast or faster than your 767.

There is also the issue of having to fit in with other traffic at busy times, and fast 737s are indeed a pain for traffic spacing at times. I have experienced more than a few 737s do a go-around because they got too close to the preceding. Never seen that with other types.
 
Max Q
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Re: 737 MAX - Pilots complain of fast landings?

Mon Mar 04, 2019 9:21 am

VSMUT wrote:
Max Q wrote:
Personally I’ve never understood the rationale for pilots complaining about higher approach speeds


We are talking 737s here, they regularly land on much smaller runways than your 767 does. They don't always have the luxury of big, wide 3 km runways. And as somebody else noted, the 737MAX lands as fast or faster than your 767.

There is also the issue of having to fit in with other traffic at busy times, and fast 737s are indeed a pain for traffic spacing at times. I have experienced more than a few 737s do a go-around because they got too close to the preceding. Never seen that with other types.




Good point, VSM, I was just looking at it from a handling standpoint


You certainly want lower approach speeds
on shorter runways
 
KICT
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Re: 737 MAX - Pilots complain of fast landings?

Mon Mar 04, 2019 10:40 am

When flown properly, aircraft does not lawndart.
 
727glasair
Posts: 78
Joined: Sat Mar 26, 2016 3:51 am

Re: 737 MAX - Pilots complain of fast landings?

Wed Mar 06, 2019 6:44 am

To Avgeek 21: A very warm welcome to you, and thanks very much for a great first post!! Great info.....you obviously know these airplanes very well.

Does the MAX feel like it has more thrust and a acceleration from zero to 100 knots? Looking forward to reading more posts from you.....thanks!
 
Avgeek21
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Re: 737 MAX - Pilots complain of fast landings?

Wed Mar 06, 2019 11:08 am

727glasair wrote:
To Avgeek 21: A very warm welcome to you, and thanks very much for a great first post!! Great info.....you obviously know these airplanes very well.

Does the MAX feel like it has more thrust and a acceleration from zero to 100 knots? Looking forward to reading more posts from you.....thanks!


You're welcome. I have not done a MAX takeoff yet that didn't need the Assumed Temperature method. So it's difficult to compare. You also have to understand the MAX 8 compared to the -800 has a different Basic Operating Weight. This depends on the individual operator's cabin configuration but the MAX 8 is between 3 and 3.5 metric tonnes heavier in our configuration. So if offsets the small thrust increase of the LEAP 1B compared to the CFM56.

The MAX is quite noticeably more efficient on sectors over 2-3 hours. Then the fuel burn starts to alter significantly compared to the -800. And when you get to 5-6+ hours it's in a class of it's own compared to the -800.

The 737 is known for it's fast approach speeds at heavy weights. It all comes down to energy management. You have to know that it is fast at times and cater for it, irrespective what ATC wants/says. And yes, I have too gone around due to a seperation that just wasn't there anymore as the preceeding was way slower. That's just a learning curve.

Boeing's issue will be the MAX 10 performance. I haven't seen any data yet but with an airframe 10 tonnes heavier at MTOW compared to the MAX 8, the same wing and engine thrust I'm guessing it will be severly performance limited compared to the A321NEO. Unless the new landing gear makes a difference and we get a thrust increase. But let's not start an A vs B flame war again. I like my Boeing and I applaud and respect the Airbus.
 
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Faro
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Re: 737 MAX - Pilots complain of fast landings?

Wed Mar 06, 2019 12:30 pm

bgm wrote:
FriscoHeavy wrote:
Contrary to another poster, it's not a compromised design. They are being silly.


Really? It's not a compromised design? How do you explain the tiny stubby landing gear (originally designed for JT8D clearance)? Look at the deformed shape of the CFM56/Leap-1B to make it fit on the wings. Or the 737 MAX 10 with the telescopic landing gear? Boeing most definitely had to make compromises to make everything fit. Look at the Leap 1A vs 1B to see the normal/deformed difference between the engines.

FriscoHeavy wrote:
As to your statement that you relayed on, are you speaking about the 737-8MAX or -9MAX? The 737-800 and -8MAX are virtually the same size. Yes, the MAX is a bit heavier, but it also sits higher off the ground and has a larger wing, so if anything, it should have better performance.


I didn't realize that Boeing had increased the wing size on the MAX? Or do you mean new winglets have increased the overall wing area a little?

Landing with a higher approach speed isn't necessarily dangerous in itself, but the airplane will be landing with much more energy that needs to be dissipated. You're far more likely to bounce/float/balloon and require consistently heavier braking/reverse thrust.

FriscoHeavy wrote:
Also, United is now able to fly the -9MAX to OGG, whereas the -900ER had performance issues. Again, this bodes well for the -9MAX and shows that it actually has better performance than it's NG predecessor.


Well, given that the Leap has ~15% improved efficiency over the CFM56, it would be a bit damning if the performance decreased. ;)
FriscoHeavy wrote:
The -10MAX will be interesting to see, but I believe it will perform better than most are willing to give it credit for.


What is your belief based on?



There is the general, generic meaning of the word "compromised" which can mean anything really...unaesthetic, more sluggish than other designs (A340), umpteenth derivative of a +50 year old design, etc.

Then there is the regulatory meaning. If anything about an aircraft model is compromised, it will definitely not be certified by the regulatory authorities.

This latter meaning is the one that counts. How do I know this? Because the MAX is selling very successfully.


Faro
 
stratclub
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Re: 737 MAX - Pilots complain of fast landings?

Wed Mar 06, 2019 3:57 pm

Avgeek21 wrote:
But let's not start an A vs B flame war again. I like my Boeing and I applaud and respect the Airbus.


What? Won't having a neutral bias in the A vs B wars get you a warning from the Mods?

Actually, I have worked Boeing 99% of my aviation career and my bias is slightly against Boeing simply because I know more about their short comings.

Like say the 727's finicky CG. If you tow a 727 backwards with no fuel and no ballast in the FWD cargo and stop quickly, they will tip over on their tail. If you defuel the center wing before defueling the wing tanks, with no ballast in the FWD cargo, they will tip over on their tale. Back in the day our night shift manager was an imbecile and over about a 3 year period had managed to tip about 5 or 6 727's over on their tails. The company owner just loved loved loved his fast and stupid approach to things.

Over all though, the 727 or any Boeing were all great aircraft to work on. Airbus? I have no clue because I have never actually worked on one but as far as I know about Airbus they do make a great product, as well.
 
FlyHossD
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Joined: Mon Nov 02, 2009 3:45 pm

Re: 737 MAX - Pilots complain of fast landings?

Wed Mar 06, 2019 4:34 pm

Avgeek21 wrote:
...Boeing's issue will be the MAX 10 performance. I haven't seen any data yet but with an airframe 10 tonnes heavier at MTOW compared to the MAX 8, the same wing and engine thrust I'm guessing it will be severly performance limited compared to the A321NEO. Unless the new landing gear makes a difference and we get a thrust increase. But let's not start an A vs B flame war again. I like my Boeing and I applaud and respect the Airbus.


The 737-10Max will have greater thrust - 31K, IIRC.
 
WIederling
Posts: 10041
Joined: Sun Sep 13, 2015 2:15 pm

Re: 737 MAX - Pilots complain of fast landings?

Wed Mar 06, 2019 4:49 pm

Avgeek21 wrote:
This depends on the individual operator's cabin configuration but the MAX 8 is between 3 and 3.5 metric tonnes heavier in our configuration.


With a similar cabin or .... ?
 
Avgeek21
Posts: 327
Joined: Mon Mar 04, 2019 5:44 am

Re: 737 MAX - Pilots complain of fast landings?

Wed Mar 06, 2019 5:39 pm

FlyHossD wrote:
Avgeek21 wrote:
...Boeing's issue will be the MAX 10 performance. I haven't seen any data yet but with an airframe 10 tonnes heavier at MTOW compared to the MAX 8, the same wing and engine thrust I'm guessing it will be severly performance limited compared to the A321NEO. Unless the new landing gear makes a difference and we get a thrust increase. But let's not start an A vs B flame war again. I like my Boeing and I applaud and respect the Airbus.


The 737-10Max will have greater thrust - 31K, IIRC.

I hope so. I believe the A321Neo has 33K on it's LEPA 1A?

WIederling wrote:
Avgeek21 wrote:
This depends on the individual operator's cabin configuration but the MAX 8 is between 3 and 3.5 metric tonnes heavier in our configuration.


With a similar cabin or .... ?
Sorry. Should have mentioned that. No, it's a very different cabin.

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