More MAX information

[Toad]

https://www.airlinepilotforums.com/2781863-post30.html

Hmmmmmmmm.

Don't know if their fleet has changed a lot over the last 10 years but Ethiopian at the moment is mostly an all Boeing fleet. They have 26 737-700 & 800 aircraft.

One would think the Captain would have learned/trained/practiced the Runaway Stab procedure while he was coming up through the ranks as SIC. I guess that's if the fleet hasn't changed much over the last 10 years.

[bustr]

The 737 MAX has an interesting parallel to the 727 back in the 60's. Due to the new wing on the 727 that slowed it down faster for landing on shorter runways, 4 of them went down in a few months due to pilots not being prepared for how fast the wing slowed the jets. The FAA supported Boeing on the design while Boeing increased training for pilots. The public forgot about it and the 727 went on to be one of Boeing's best selling items.

https://www.cnn.com/2019/03/19/business/boeing-727-crash-lessons/index.html

I suspect Trump grounded the fleet due to Boeing giving his election committee a $1M donation in 2016 to keep them from going through a media colonoscopy witch hunt trying to harm them for the donation. Boeing will weather this since they have orders for 5000 737 MAX generation jets since 2011. I found the results of simulator tests of what is suspected to be the root cause of the two accidents. Pilots had 40sec to correct for it to save the plane, in the simulator the pilots made the correction in time. Boeing is shipping a patch for the MCAS and providing pilot training. Everywhere I have read discussions, the update to the MCAS and more pilot training is what most see as the solution. Good parallel to the 727 accident problem due to a new technology pilots were not trained adequately for.

As for the discussion of pilot quality and competence as a generational problem, HAL must be laughing to himself. Both the 727 and 737 accidents were due to making the cost of flight cheaper and more profitable. Humans are always the most expensive part of the equation and the source of most mishaps over the long run. At least AI only piloted jets are not being pushed as the answer for these current accidents. But, the more we rely on tech, it is being found the less reliable we become when we have to get our hands dirty.

[Vraciu]

I have no idea what “wings that slow the plane faster” is supposed to mean. 

The 727 was extremely slick and had a very high cruise speed for its day.   With massive high lift devices to allow for it to land at non-Concorde speeds and engines that were not very quick to spool from low thrust settings it was easy to get behind the power curve.   They didn’t call it “The Rubber-Tired Jackhammer” for nothing.

[Puma44]

One would think the Captain would have learned/trained/practiced the Runaway Stab procedure while he was coming up through the ranks as SIC.

My thought also.  As I alluded to in my simulator checkride post, the runway stab trim can be quite a surprise but, can be handled.  Makes me wonder if these guys were surprised and got too far behind the jet.

[Arlo]

I have no idea what “wings that slow the plane faster” is supposed to mean. 

[Vraciu]

(Image removed from quote.)

That’s not the answer. 

The 727 had a high speed wing with a high degree of sweepback.   (I flew the “727, jr.” also known as the Citation III, for a little bit FWIW.   Funny story how the latter was basically a twin-engine clone of the 727.  Even the APU inlet on the III was round like the center engine on the Boeing.)

If they’re talking about the flap system inducing drag quicker than previous jets that might make sense.   But the author of that article is not even a layman.    His word salad wasn’t remotely understandable. 

[Arlo]

That’s not the answer. 

The 727 had a high speed wing with a high degree of sweepback.   

If they’re talking about the flap system inducing drag quicker than previous jets that might make sense.   But the author of that article is not even a layman.    His word salad wasn’t remotely understandable.

I found an airfoil graphic, which, to me, perfectly illustrated "“wings that slow the plane faster." Didn't read the article you don't understand. 

[Vraciu]

I found an airfoil graphic, which, to me, perfectly illustrated "“wings that slow the plane faster." Didn't read the article you don't understand. 

Again.  How does a 727 have “a wing that slows the airplane faster” than previous jets as the author implies?

Makes no sense. 

[Arlo]

Again.  How does a 727 have “a wing that slows the airplane faster” than previous jets as the author implies?

Makes no sense.

Listen, my guess was airfoil design. If you don't find satisfaction in that then you'll hafta ask an expert. 

[Vraciu]

Listen, my guess was airfoil design. If you don't find satisfaction in that then you'll hafta ask an expert. 

I am an expert. 

I also know how to write fairly well.    This author...  “Wings that slow the airplane faster.”

That’s not even a criteria for landing on a short runway in a jet.  You expect to be stabilized at 1000’ for instrument, 500’ for a visual.   If you have to “slow the airplane faster” you’re behind.   Go around. 

It’s probably those giant flaps on the 727 he was attempting to reference.  If you got behind the curve the Cessna 150 was bad that way, too, at flaps 40.    Thing would drop like a brick and was too underpowered to arrest the descent.   *Wham!*

(Edited to clarify.  Original quoted below.)

[Vraciu]

I am an expert. 

I also know how to write fairly well.    This author...  “Wings that slow the airplane faster.”

That’s not even a criteria for landing on a short runway in a jet.  You expect to be stabilized at 1000’ for instrument, 500’ for a visual.   If you have to “slow the airplane faster” you’re behind.   Go around. 

It’s probably those giant flaps on the 727 he was attempting to reference.  The Cessna 150 was bad that way, too, at flaps 40.    Thing would drop like a brick.

Assuming Wiki is accurate—always a gamble.   Go figure.  Flaps 40.

The 727 was stable at very low speeds compared to other early jets, but some domestic carriers learned after review of various accidents that the 40-degree flap setting could result in a higher-than-desired sink rate or a stall on final approach. These carriers' Pilots' Operation Handbooks disallowed using more than 30° of flaps on the 727, even going so far as installing plates on the flap lever slot to prevent selection of more than 30° of flaps.

Edit in:

Looks about right.  Better article any way regarding the early days of the 727.

https://www.tmtindustryinsider.com/2016/08/air-safety-the-deadly-boeing-727/

(T)he Civil Aeronautics Board (the CAB, which was responsible for investigating air accidents and making safety recommendations at that time) undertook a review of the 727’s airworthiness, aerodynamics and flight characteristics.  It also requested the National Aeronautics and Space Administration to review the 727 design data.  And the Federal Aviation Agency (FAA) convened a meeting of 727 operators to review their operating procedures and training.

The result of these reviews was a conclusion that the 727 was airworthy and properly certificated. However, the CAB found that pilots were making unstabilized, high descent rate approaches more often in 727s than in any other jet transport—a practice that was facilitated by the 727’s sophisticated flap system, which allowed excessive sink rates to develop if approaches were not carefully monitored.

While these reviews were in progress the CAB issued its report on the Cincinnati accident. It found the probable cause to be failure of the crew to properly monitor the altimeters during a visual approach in deteriorating weather conditions. The flight data recorder showed a high airspeed and a decent rate of more than 2,000 feet per minute in the final stages of the approach, far in excess of the permitted maximum. Similarly, the CAB found that the probable cause of the Salt Lake City crash was the captain’s failure to take timely action to arrest an excessive rate of descent during the landing approach.

In response, the FAA required the airlines to make changes to their training procedures and their flight manuals to stress the importance of stabilized approaches.

The landing accidents ended.

(Edited for punctuation and php/html styling code.)

[Toad]

Ok, I think it must be Flaps 40 on the B-727.

I had the opportunity to fly it (727-200) before and after the company decided to put the blocking plate over the Flaps 40 selection.

First: You don't fall out of the sky and die if you use Flaps 40. We used it pretty much routinely going into short fields.

Second: It did require that you pay attention; 40 was a lot of drag and you didn't want to get slow/behind the power curve.

Third: Pulling power quickly resulted in a "land NOW" command. You eased the power off.

Fourth: You felt like you were hovering on short final with 40 out.

Fifth: The peeps sitting in the window seats by the trailing edges probably thought the wing was totally coming apart. You could see a LOT of daylight.

Great airplane.

[Vraciu]

Sounds right to me.   

[Puma44]

The “Land Now” command; Classic!

[Busher]

Seems Mr.Toad has been around a while too.

727-200 time even before most airlines blocked the 40 flap selection.

<S> Sir.