16
$\begingroup$

This question already has an answer here:

I’m flying on a WestJet Boeing 737-800 from Honolulu to Vancouver and then on to Toronto in July, returning on the same type of aircraft in August. Are these aircraft still grounded and are they similar to the MAX 8?

$\endgroup$

marked as duplicate by bogl, fooot, Jamiec Apr 29 at 15:18

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • 7
    $\begingroup$ Is the 737-800 a different plane from the 737 MAX 8? $\endgroup$ – ymb1 Apr 28 at 8:48
  • 4
    $\begingroup$ This isn't a duplicate. The other question only covers the fact that the -800 and MAX 8 are different planes. That doesn't answer the question of whether the -800 is also grounded. $\endgroup$ – David Richerby Apr 28 at 17:20
  • 1
    $\begingroup$ It really is the same question, the question of whether they are also grounded is incidental. FWIW, they are not also grounded. $\endgroup$ – Jamiec Apr 29 at 15:19
53
$\begingroup$

The 737-800 is not grounded (and never has been). The aircraft type has an excellent safety record. Since 1997 over 5000 have been produced.

The 737 MAX 8 is its successor. The aircraft is very similar to the 737-800. One of the differences is the placement (more forward and higher) of the slightly bigger engines. This changed the stability of the aircraft under certain flight conditions, causing Boeing to introduce the Maneuvering Characteristics Augmentation System (MCAS). The MCAS played a crucial role in two recent crashes of the 737 MAX 8, leading to the grounding of the aircraft type.

The 737-800 does not have such a system and is therefore not affected.


Airlines typically use IATA aircraft codes (3 letters) or ICAO aircraft type designators (4 letters) to indicate the aircraft type used on the flights.

For the Boeing 737-800 the ICAO type designator is B738, while the IATA codes are 738 and 73H.

The Boeing 737 MAX 8 has the ICAO type designator B38M and IATA code 7M8.

$\endgroup$
  • 9
    $\begingroup$ @Cloud Not every Boeing is a 737 MAX; Boeing makes other aircraft types that hold excellent safety records. And if you compare the safety records of the 737 MAX to the safety records of the A320 two years after its entry into operation, you will see that the MAX accumulated more flight hours after its first two fatal accident (JT610 & ET302) than the A320 did (AF296 & IC605). In both A320 accidents as well as both B737 MAX accidents the pilot's awareness & understanding of the automation played big role. It's sad to see that Boeing is learning some of the same lessons again after 30 years. $\endgroup$ – DeltaLima Apr 29 at 11:55
  • $\begingroup$ Totally agree, but what I mean it Airbus has no new systems implemented recently, so it's just the safest option at the moment. If I am booked to fly on an A320 and the airline changes it last minute, I will refuse boarding and demand a refund. $\endgroup$ – Cloud Apr 29 at 13:53
10
$\begingroup$

The 737-800 is cleared to fly, and thousands fly every day.

Only the latest design revision, the 737-8 Max or "Max 8" are grounded, due to suspicion of a new automation system. (and also the Max 7 and 9).

The 737 is the most-produced jetliner in the world, with 3 major design revisions and many updates over decades. That design is extremely well refined and proven. Because of that, the newer versions like the -800 are particularly safe.

So what's all the fuss about?

The 737 itself is a refinement of earlier jets, and the "engines under wing" layout harkens back to the original production jet: the Messerschmitt 262.

Have you ever made a transition from a rear-wheel-drive car to a front-wheel-drive car? You might have noticed when you punch the gas, the car "pulls" a little to the left. You correct that with the steering wheel, and you hardly notice because you're already making steering wheel corrections all the time. It's automatic, unconscious.

The amount of that "torque steer" varies in different conditions (slow vs fast) and different cars and different engines in the same car (4-cylinder vs V-6). But nobody has to go back to driving school for it, do they?

Airplanes have things like that. Particularly, engine-under-wing aircraft have the thrust line below the center of gravity... so punching the gas will make the airplane tilt upward a bit. Just like your car's torque steer, it varies between speeds, altitudes, airplane model etc. And just like you, the pilot corrects for it at the wheel. No big deal.

enter image description here

Almost all jetliners are like this.

Compared to your airplane, the 737 MAX 8 has slightly bigger engines, which makes this effect a little more. And it's such a small change to the 737, that the (very reasonable) argument is that pilots shouldn't have to go back to flight school to learn how to fly the same airplane with a slightly bigger engine. Unfortunately, somebody decided this little extra bit crossed a line.

They had something of a case, because under rare conditions (high nose-up and low speed and ...) those bigger engines could cause a balance issue, making the controls feel soft, and that might confuse pilots. Imagine if you're going around a cloverleaf in your car, climbing a hill at 20 mph and suddenly you need more steering wheel than you expect. The new system (MCAS) added a bit of nose-down "trim" to help the airplane feel normal. FAA decided this was required to certify the plane.

Mind you, this part is about the MAX, not your airplane.

But when you add a whole new system, you add a whole new way for that system to fail. We don't know the answer, and accident speculation isn't what we do here, but all the evidence so far is pointing to an unexpected problem there.

Mind you, aircraft designers expect problems and design for every failure mode they can anticipate - and they did their diligence in this system too. It was designed to fail in a way that pilots already know how to fix*. Apparently this hasn't worked, and "why not" is the question of the hour.

It's all part of some very hard questions being faced in aviation about whether automation makes things better or worse. We're facing these hard problems because aviation has solved all the easy problems. They just don't have accidents the way they used to. Southwest practically proves the rule: America's safest and busiest carrier, they have had an all-737 fleet since 1971***. They have the largest 737 fleet in the world, and each plane averages 6 takeoff/landings a day.




* The up/down trim can be worked with either handwheels or pushing a switch that lets electric motors turn the handwheels for you. It's always been possible for that switch to get stuck or shorted, running the trim to the extreme position. The motors are intentionally weak and you can grab the wheels and stop/overpower them. There is also a switch to turn them off, right on the console. And that switch hasn't moved since 1967.

*** In the 1980s they leased a few 727's. But that's it.

$\endgroup$
  • 4
    $\begingroup$ Downvoter keep in mind I'm writing this for OP, who is a nervous flier. I am not writing this for aviators. That makes me very vulnerable to highly technical nitpicking, but that is unfair and unconstructive given the audience. $\endgroup$ – Harper Apr 28 at 16:45
  • $\begingroup$ I'm downvoting because this is accident speculation and has a whole paragraph about Fukushima, which is completely unrelated to the question. $\endgroup$ – Dan Hulme Apr 29 at 9:25
  • $\begingroup$ This answer seems at odds with what we read in the media, which is that the crashes occurred due to a malfunction of a sensor, and that the pilots were indeed trying to compensate for it. Is the media misreporting? $\endgroup$ – JBentley Apr 29 at 13:03
  • $\begingroup$ @DanHulme Fukushima - gone. It barely had any accident speculation, and I've sanitized even that. I don't know what you're looking for, honestly. $\endgroup$ – Harper Apr 29 at 14:32
  • 1
    $\begingroup$ "Make it as simple as possible, but not simpler" ─ this seems to have gone past the line, I should think. This answer definitely looks like it's mischaracterizing the circumstances in which the MCAS was thought necessary, particularly given the fact that the new engine placement significantly reduced the dynamic stability of the aircraft. It's not just a quantitative change: in your analogy, it's a car where if you let the torque steering go past a small amount, then the car will spontaneously throw itself into a tailspin. $\endgroup$ – E.P. Apr 29 at 15:02
4
$\begingroup$

The 737-800 is not grounded; it is a different aircraft to the 737 MAX 8. The -800 was introduced in 1998; the MAX 8 in 2016.

$\endgroup$
  • 7
    $\begingroup$ This doesn't seem to add anything new to this answer (apart from the reference to 2016) and doesn't address the question about similarities between the aircraft (which the other answer already does). $\endgroup$ – JBentley Apr 27 at 23:45
0
$\begingroup$

Both crashes that led to grounding of 737 MAX were caused by malfunctions related to MCAS which is not present in the 737-800.

So if it's a safety concern you should rest assured. 737-800 has an outstanding record for safety.

$\endgroup$
  • 8
    $\begingroup$ This answer adds nothing that is not in DeltaLima's answer 18 hours prior. $\endgroup$ – dotancohen Apr 28 at 6:12

Not the answer you're looking for? Browse other questions tagged or ask your own question.