# Breaking News: Plane lands safely in CO after dropping parts **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [February 20, 2021, 9:44pm UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364 "2021-02-20T21:44:40Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Monty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/monty/32/47_2.png) [@Monty](https://boards.straightdope.com/u/Monty)\ **Post date:** [February 21, 2021, 2:28am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/21 "2021-02-21T02:28:22Z")
According to [“Ask a Pilot”](https://www.johnnyjet.com/what-does-heavy-mean/#:~:text=When%20a%20pilot%20uses%20the,it%20and%20the%20aircraft%20following.), it refers to the size (weight) of the aircraft and wake turbulence, meaning ATC needs to know so they can keep the following airplanes separated the correct distance. ---
**Author:** ![WildaBeast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wildabeast/32/6_2.png) [@WildaBeast](https://boards.straightdope.com/u/WildaBeast)\ **Post date:** [February 21, 2021, 2:29am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/22 "2021-02-21T02:29:22Z")
> [@OldGuy](#): > > When they refer to the flight as 328 heavy what does heavy mean? The actual pilots here can probably explain it better, but all planes above a certain maximum takeoff weight (regardless of how heavy they actually are at that moment) are referred to as “heavy” by ATC. It serves as a warning to other planes in the area to maintain greater separation, because big planes generate more wake turbulence that small ones. IICR the “heavy” label applies to all widebody aircraft, as well as some versions of the 757. And I think there’s a special designation for the A380, since it generates even more wake turbulence than a typical widebody. ---
**Author:** ![DCnDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dcndc/32/2842_2.png) [@DCnDC](https://boards.straightdope.com/u/DCnDC)\ **Post date:** [February 21, 2021, 3:32am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/23 "2021-02-21T03:32:37Z")
Anyone in the area with an unusual surname, like “Darko” perhaps? ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [February 21, 2021, 7:44pm UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/24 "2021-02-21T19:44:22Z")
> [@WildaBeast](#): > > The actual pilots here can probably explain it better, but all planes above a certain maximum takeoff weight (regardless of how heavy they actually are at that moment) are referred to as “heavy” by ATC. It serves as a warning to other planes in the area to maintain greater separation, because big planes generate more wake turbulence that small ones. IICR the “heavy” label applies to all widebody aircraft, as well as some versions of the 757. And I think there’s a special designation for the A380, since it generates even more wake turbulence than a typical widebody. Exactly. The corresponding term for A380 & larger airplanes (assuming any other such behemoths are ever built) is “super” as in “Denver Approach, Lufthansa 328 super at one two thousand feet.” ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [February 22, 2021, 1:48am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/25 "2021-02-22T01:48:13Z")
And in an oddly timed coincidence, in the Netherlands [a 747 cargoliner landed safely after pieces fell off during an engine fire, slightly injuring two people on the ground.](https://www.cnn.com/2021/02/21/europe/cargo-plane-debris-meerssen-netherlands-trnd/index.html) ---
**Author:** ![Gray\_Ghost](https://avatars.discourse-cdn.com/v4/letter/g/c0e974/32.png) [@Gray\_Ghost](https://boards.straightdope.com/u/Gray_Ghost)\ **Post date:** [February 22, 2021, 6:33am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/26 "2021-02-22T06:33:42Z")
> [@Kent\_Clark](#): > > And in an oddly timed coincidence, in the Netherlands [a 747 cargoliner landed safely after pieces fell off during an engine fire, slightly injuring two people on the ground.](https://www.cnn.com/2021/02/21/europe/cargo-plane-debris-meerssen-netherlands-trnd/index.html) Powered by a Pratt & Whitney PW-4000 series engine. Well, four of them. Kissing cousin to the PW-4000 series in the UA Flight 328 777. So, the FAA is a little displeased. FAA President just issued an Emergency Airworthiness Directive for the PW-4000 series engines in certain 777s. Statement viewable [here](https://mobile.twitter.com/jonostrower/status/1363632056861777925). “Immediate or stepped-up inspections” of those engines, “likely mean[ing] that some airplanes will be removed from service.” Not a good day. I hope they find whatever is wrong. If there’s anything at all. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [February 22, 2021, 12:20pm UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/27 "2021-02-22T12:20:15Z")
Great play-by-play commentary from takeoff to touchdown by Captain Joe here: [![](https://img.youtube.com/vi/q5Wler87pwY/maxresdefault.jpg "UNITED 328 Engine Failure! WHAT CHECKLISTS did the pilots use? Explained by CAPTAIN JOE") ](https://www.youtube.com/watch?v=q5Wler87pwY) ---
**Author:** ![TimothyNewsome](https://avatars.discourse-cdn.com/v4/letter/t/7ba0ec/32.png) [@TimothyNewsome](https://boards.straightdope.com/u/TimothyNewsome)\ **Post date:** [February 22, 2021, 6:10pm UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/28 "2021-02-22T18:10:51Z")
Maybe it is time to get rid of your Boeing stock, as yet another of their planes (this time a 747) started losing parts midflight, dropping wreckage that injured two unlucky devils on the ground (as well as some houses and cars) in the Netherlands, although thankfully like the 777, the plane managed to safely make an emergency landing, this time apparently somewhere in Belgium. Perhaps the jetpack guy in LA has the right idea. ---
**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\ **Post date:** [February 22, 2021, 6:43pm UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/29 "2021-02-22T18:43:05Z")
Maybe you should read reports more carefully - apparently this is an issue with a particular engine that is mounted in some Boeing airplanes and not the Boeing airframe design. But do go ahead and unload your stock so others who are more informed can purchase shares cheaply and reap the benefits when this is sorted out and Boeing is on an upswing again. Or maybe, not being an expert in any of this, I’m wrong. Just sayin’ stock tips off an internet forum should be taken with a very large lump of salt. ---
**Author:** ![WildaBeast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wildabeast/32/6_2.png) [@WildaBeast](https://boards.straightdope.com/u/WildaBeast)\ **Post date:** [February 22, 2021, 6:58pm UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/30 "2021-02-22T18:58:12Z")
> [@Broomstick](#): > > Maybe you should read reports more carefully - apparently this is an issue with a particular engine that is mounted in some Boeing airplanes and not the Boeing airframe design. Indeed, and and for that matter the PW4000 is also one of the engine options on the Airbus A330 (and A300 and A310, but I don’t think there are many of those in service anymore, except maybe hauling cargo). Also, I think the PW4000 was actually a relatively unpopular engine option on the 777, although I’d have to look up the relative numbers. I’m pretty sure the majority of 777s use either GE or Rolls Royce engines, and are thus unaffected by the Emergency Airworthiness Directive. IIRC United is one of the few major users of P&W engines on the 777. ---
**Author:** ![WildaBeast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wildabeast/32/6_2.png) [@WildaBeast](https://boards.straightdope.com/u/WildaBeast)\ **Post date:** [February 22, 2021, 7:29pm UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/31 "2021-02-22T19:29:30Z")
> [@WildaBeast](#): > > Also, I think the PW4000 was actually a relatively unpopular engine option on the 777, although I’d have to look up the relative numbers. I missed the edit window, but I found a cite for the quote above. > Boeing said there were 69 777s with the Pratt & Whitney 4000-112 engines in service and another 59 in storage. So yeah, relatively few 777s use that type of engine. Source: > **[Boeing: 777s with engine that blew apart should be grounded](https://apnews.com/article/boeing-777-grounded-0c08e256cc210cf6d71b8e0cdd26c543)** > > Boeing has recommended that airlines ground all 777s with the type of engine that blew apart after takeoff from Denver this past weekend, and most carriers that fly those planes said they would temporarily pull them from service. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [February 23, 2021, 2:05am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/32 "2021-02-23T02:05:45Z")
PW4xxx engines were not a huge commercial success. But they’re used on some small fraction of B757s, B767s, B777s, A300s, A310s, and A330s. Plus a bunch of USAF airplanes. Agree with @Broomstick that this is a P&W issue, not a Boeing issue. Boeing will catch some heat, but P&W is the one on the hook for all the remediation costs. ---
**Author:** ![Gatopescado](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gatopescado/32/5711_2.png) [@Gatopescado](https://boards.straightdope.com/u/Gatopescado)\ **Post date:** [February 23, 2021, 6:24am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/33 "2021-02-23T06:24:25Z")
I read this as “dropping pants”. ---
**Author:** ![X.L.Lent](https://avatars.discourse-cdn.com/v4/letter/x/a5b964/32.png) [@X.L.Lent](https://boards.straightdope.com/u/X.L.Lent)\ **Post date:** [February 24, 2021, 11:49pm UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/34 "2021-02-24T23:49:43Z")
How long could the plane stayed in the air after the engine exploded? In the video it looks like the engine was vibrating badly after the explosion. Could metal fatigue cause the damaged engine to break off of the wing? Glad that no one was killed or injured. It seems fortunate that this occurred over land and not over the middle of the ocean. ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [February 25, 2021, 12:25am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/35 "2021-02-25T00:25:39Z")
How long? In general for hours. The flight was scheduled for about 7 hours in the air, so they had that much fuel. Burn rate is higher at low altitude, but one engine can be more efficient than two. So maybe only 5 hours circling around Denver at relatively low altitude. Whether vibrations would eventually rip the engine off is strictly unanswerable but is very unlikely. This is very far from the first such failure on long haul jets in general. The engine wasn’t doing much good where it was, and in fact things might have gotten better, not worse, had it off broken off cleanly. Which they are designed to do if the loads get excessive, rather than wrenching out a big hunk of wing along the way. In general, engine failures in flight are not high hazard events. Even those where parts get shed. Certianly much riskier than a flight where nothing goes wrong, but having an engine come apart mid-ocean is a major annoyance, but no reason for people to think death is certain and survival a miracle. More the opposite. Interestingly, per NTSB today, they are considering this a _contained_ engine failure, at least for now. The engine parts all stayed inside the engine case and were ejected out the back as designed. It was the comparatively flimsy cowling parts that came apart and punched some minor holes in the unpressurized part of the fuselage. There definitely _is_ concern about cowlings coming apart too readily. There’s a wildcard there that we don’t have good engineering on. ---
**Author:** ![mikecurtis](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mikecurtis/32/3284_2.png) [@mikecurtis](https://boards.straightdope.com/u/mikecurtis)\ **Post date:** [February 25, 2021, 12:35am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/36 "2021-02-25T00:35:27Z")
> [@LSLGuy](#): > > The engine wasn’t doing much good where it was, and in fact things might have gotten better, not worse, had it off broken off cleanly. That’s a lot of weight to lose off one side of a plane. Why wouldn’t it just roll like [this one](https://en.wikipedia.org/wiki/American_Airlines_Flight_191) ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [February 25, 2021, 12:45am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/37 "2021-02-25T00:45:03Z")
No, not like that. Decent thinking on your part, but not correct. The thrust of the good engine makes the airplane want to turn towards the bad engine. If the bad engine fell off cleanly the lack of weight of the bad engine is a counterbalancing force that makes the overall situation more balanced, not less. AA191 you linked to was a much different situation. They were just after liftoff and very slow. They had the wing flaps deployed to the takeoff setting which includes having leading edge flaps/slats deployed along the full span of the wing. > **[Leading-edge slat](https://en.wikipedia.org/wiki/Leading-edge_slat)** > > Pages for logged out editors learn more > > Slats are aerodynamic surfaces on the leading edge of the wing of a fixed-wing aircraft which, when deployed, allow the wing to operate at a higher angle of attack. A higher coefficient of lift is produced as a result of angle of attack and speed, so by deploying slats an aircraft can fly at slower speeds, or take off and land in shorter distances. They are used during takeoff and landing or while performing low speed maneuvers which may take the ... When AA 191’s left engine broke off it pivoted up and over the front of the wing, passing _over_ the wing before falling to Earth. In the course of that it tore a massive hole in the deployed leading edge flaps/slats and ripped out a bunch of hydraulics. Which lack of hydraulic pressure then caused _all_ the leading edge flaps on that wing to retract. That massively increased the stall speed of that one wing, but not the other one that was unaffected. The left wing promptly stalled and the airplane rolled over and died. Had they been 50 knots faster they could have recovered from the lift asymmetry of two differently flying wings; but as slow as they were they had one completely unflyable wing and the ground only seconds away. That combo was not recoverable. ---
**Author:** ![mikecurtis](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mikecurtis/32/3284_2.png) [@mikecurtis](https://boards.straightdope.com/u/mikecurtis)\ **Post date:** [February 25, 2021, 1:23am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/38 "2021-02-25T01:23:27Z")
Thanks for that explanation. As always you can be counted on to make it understandable for us land lubbers. Personal anecdote about AA191: I grew up in Des Plaines and was attending a high school less than a mile from the crash site. I did not see the crash but several of my friends, who were outside for gym class and had an unobstructed view. As you can imagine, even in the time before cell phones, that news spread through the entire school within about 5 mins. ---
**Author:** ![X.L.Lent](https://avatars.discourse-cdn.com/v4/letter/x/a5b964/32.png) [@X.L.Lent](https://boards.straightdope.com/u/X.L.Lent)\ **Post date:** [February 25, 2021, 6:13am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/39 "2021-02-25T06:13:16Z")
Thank you [LSLGuy](https://boards.straightdope.com/u/LSLGuy) for your excellent answer to my question. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [February 25, 2021, 11:42am UTC](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364/40 "2021-02-25T11:42:00Z")
> [@mikecurtis](#): > > That’s a lot of weight to lose off one side of a plane. Why wouldn’t it just roll like [this one](https://en.wikipedia.org/wiki/American_Airlines_Flight_191) LSLGuy has provided an excellent explanation. The visual confirmation is in the pre-crash photo, seen **[here](https://en.wikipedia.org/wiki/American_Airlines_Flight_191#/media/File:Aa191_ohare.jpg)**: note that the heavy wing, the one still holding an engine, has rolled up rather than down. [Previous page](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364.md?page=1) [Next page](https://boards.straightdope.com/t/breaking-news-plane-lands-safely-in-co-after-dropping-parts/933364.md?page=3)