# The Great Ongoing Aviation Thread (general and other) (Part 1)
**URL:** https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499
**Category:** Miscellaneous and Personal Stuff I Must Share
**Created:** [October 23, 2011, 2:17am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499 "2011-10-23T02:17:01Z")
**Posts on this page:** 20
**Page:** 313
### Author:  [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)
#### Post date: [June 21, 2024, 8:38pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6243 "2024-06-21T20:38:13Z")
Oh absolutely! An inspection to determine what likely works and what doesn’t, including lots of functional and operational tests. Repairs on-site by mobile repair teams for critical systems. Then establishing limitations under which the aircraft can still fly for a ferry flight (note from a legal perspective the aircraft isn’t “airworthy” but it can still be operated under alternative procedures and limitations). Then the plane would be ferried to an appropriate repair shop (if one isn’t at this particular airport, naturally that’s a better choice) for complete repairs and return to a certified and airworthy state.
Using an example I’ve supported for a customer, you can’t dispatch normal operations without a functional total fuel quantity indicator. But you can ferry the plane by ensuring you have extra fuel in each tank, by prohibiting fuel cross flow between tanks, by monitoring each engine fuel burn, by limiting bank angles to avoid an undetected weight imbalance in each wing, etc. The plane requires more attention, but can still fly under a ferry permit.
I’d have to spend a lot of time inventing a hypothetical and coming up with allowances for this type of paint spray, but it can be done and is done pretty frequently because shit breaks!
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### Author:  [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)
#### Post date: [June 21, 2024, 8:39pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6244 "2024-06-21T20:39:15Z")
Oh and bizjets are often rather modern in terms of automation; the customers love the latest and greatest.
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### Author:  [@Robot\_Arm](https://boards.straightdope.com/u/Robot_Arm)
#### Post date: [June 21, 2024, 8:47pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6245 "2024-06-21T20:47:09Z")
I don’t doubt that they have all the automated bells and whistles, but are they as reliant on them as modern airliners? If you didn’t trust the sensors that were sending data to the autopilot, could you fly a bizjet purely by hand and backup gauges?
(Yeah, the backup gauges probably can’t be trusted, either.)
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### Author:  [@Llama\_Llogophile](https://boards.straightdope.com/u/Llama_Llogophile)
#### Post date: [June 21, 2024, 9:12pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6246 "2024-06-21T21:12:13Z")
> [@](#):
>
> I don’t doubt that they have all the automated bells and whistles, but are they as reliant on them as modern airliners? If you didn’t trust the sensors that were sending data to the autopilot, could you fly a bizjet purely by hand and backup gauges?
There’s quite a range of equipment in the bizjet world. Planes manufactured more recently generally have more modern automation, as one would expect. But one of the planes I have experience in was built decades ago, though many have been upgraded with very modern avionics suites. So it’s an interesting mixture of an old airframe blended with newer instrumentation.
So in that plane any failures would be more or less the same as in most modern aircraft. The pitot tubes and static ports send their data to redundant air data computers, although some raw data is also sent to standby instruments.
I remember not long ago poking my head into a bizjet built in the 1950s that was mostly unchanged. On the one hand, that creates burdens for pilots nowadays who are used to more help from their avionics. But OTOH, failures were probably a bit more straightforward because they didn’t have computers standing between them and the raw data.
Remember, even great automation adds complexity. That Airbus that went down over the Atlantic some years ago was a case in point - without going into details I suspect it might not have happened in a Boeing. A lot of faults I encounter these days as a pilot are automation / instrumentation related, and it requires some real parsing of the checklist and knowledge of the systems to figure out what’s happening.
Edit: I didn’t really answer the last question. Yes, you can fly a modern jet by hand on backup instruments. It’s no fun though, I can tell you that. In the simulator I’ve had occasion to hold a flashlight on the backup instruments so my partner could see what they were doing. Thankfully, I’ve never encountered that situation in real life.
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### Author:  [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)
#### Post date: [June 21, 2024, 9:18pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6247 "2024-06-21T21:18:51Z")
They often share technology actually; when looking at new tech you often get adapted instrumentation (from a software and computer hardware perspective) that’s existing in the commercial sector. When Collins or Honeywell says “this is the unit we have, we can adapt these parameters” you kind of design from there (yes, there’s more customization possible, but there’s starting baseline implementations for a bunch of stuff).
There aren’t any “gauges” on a Global 7500. There isn’t even a CB panel, they’re electronic circuit breakers. I have no idea how that works though, electricity is magic as far as I’m concerned.
The cockpit of a late Challenger 601 is pretty much the same as that of an early CRJ-100/200. They’re siblings, from a design perspective.
I’m not a pilot - trust me, you wouldn’t want me to be one - but the “reliance” on tech is the same if not higher because all the tech is available.
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### Author:  [@Llama\_Llogophile](https://boards.straightdope.com/u/Llama_Llogophile)
#### Post date: [June 21, 2024, 9:25pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6248 "2024-06-21T21:25:17Z")
> [@mnemosyne](#):
>
> There aren’t any “gauges” on a Global 7500. There isn’t even a CB panel, they’re electronic circuit breakers. I have no idea how that works though, electricity is magic as far as I’m concerned.
Whoo boy, I’ve flown one plane that had a mixture of physical and “virtual” circuit breakers and I didn’t like it. Quick story for those who are interested:
We were on the ground getting ready to fly passengers and the computers were throwing a fault of some kind. The checklist was no help, and neither was the in-house troubleshooting document we had that contained tribal knowledge on what to do in certain situations.
It wasn’t looking good. Even a complete restart didn’t clear it. While my partner was on the phone with maintenance I began paging through the virtual circuit breakers. There were many dozens of them and none seemed relevant. On about page 8 I found one that was flagged as tripped. I called over my partner over, pointed to it and said I hadn’t made any changes yet.
He nodded and I told the computer to reset it. It did and suddenly the fault cleared. Maintenance decided it was kosher and we flew the trip. But we never did find out why that fault occurred or why that particular virtual breaker was the problem. But only a manual search found it, and no checklist directed us there.
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### Author:  [@mnemosyne](https://boards.straightdope.com/u/mnemosyne)
#### Post date: [June 21, 2024, 9:27pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6249 "2024-06-21T21:27:54Z")
I hope you/maintenance reported it to the OEM so that they could create a procedure and update their manual! I’ve also supported lots of that - and raised my own comments several times too!
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### Author:  [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)
#### Post date: [June 22, 2024, 8:19pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6250 "2024-06-22T20:19:48Z")
Yeah…there are no details but this seems more like pilot error than a malfunction in the plane.
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### Author:  [@Magiver](https://boards.straightdope.com/u/Magiver)
#### Post date: [June 23, 2024, 9:32am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6251 "2024-06-23T09:32:50Z")
[Another Lockheed 12A crash.](https://www.youtube.com/watch?v=sQhA-R2kKbo) All 3 aboard survived. Full video of the landing on a grass strip. Looks like they forgot to lock the tail wheel.
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### Author:  [@Al128](https://boards.straightdope.com/u/Al128)
#### Post date: [June 23, 2024, 9:43pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6252 "2024-06-23T21:43:15Z")
Interesting (2.00 min) video of a spark plug being changed in a commercial airliner: (reddit video)
[https://www.reddit.com/r/interestingasfuck/comments/1dmlb12/changing\_a\_spark\_plug\_in\_a\_turbine\_engine/](https://www.reddit.com/r/interestingasfuck/comments/1dmlb12/changing_a_spark_plug_in_a_turbine_engine/)
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### Author:  [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)
#### Post date: [June 23, 2024, 10:09pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6253 "2024-06-23T22:09:32Z")
Two days ago I rode in a light plane, a 172, for the first time since about 2005. That previous event ~19 years ago was two rides in a Cherokee Six, up to a business meeting and back home the same day. The time before that was flying my own plane, a Twin Comanche, back around 1998 shortly before we sold it.
Evidently lightplane GA is not gonna survive on my use of it. But it was fun and nostalgic. And really, really rickety and primitive.
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### Author:  [@PastTense](https://boards.straightdope.com/u/PastTense)
#### Post date: [June 24, 2024, 4:47pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6254 "2024-06-24T16:47:49Z")
> **[Federal prosecutors recommend to Justice Department that Boeing be criminally...](https://www.cbsnews.com/news/boeing-criminal-charges-recommendation/)**
>
> Prosecutors have recommended the Justice Department should criminally prosecute Boeing for allegedly violating a deferred prosecution agreement from 2021.
I think it doubtful anything will happen.
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### Author:  [@Raza](https://boards.straightdope.com/u/Raza)
#### Post date: [June 24, 2024, 6:37pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6255 "2024-06-24T18:37:30Z")
To put some closure on this Allentown GA fatal accident:
The final report came out this month (June 5 2024) for the September 28 2022 accident. Bottom line: they don’t know what the root cause was (severe post-accident fire damage), but the proximate cause is believed to be simply insufficient engine power.
Reading through the NTSB narrative reconstruction of events, my ancient low-time pilot assessment is: _if you’re on a takeoff roll and things don’t seem right, and there’s runway left, ABORT!_.
Recap:
KXLL paved 4,000 ft runway, Piper PA-28 single engine, instructor 1350 total hours and student **51** total hours; plane crashed about a mile from the end of the runway, where it burst into flames; student killed, instructor severely injured.
The report is a downloaded PDF so not easy to link, but here are some snippets (bolding mine):
> [@](#):
>
> The instructor stated that, during the takeoff, **the airplane had not become airborne by the time he felt it should** , and he prompted the student to increase the airplane’s pitch attitude and it became airborne. The student then **reduced** pitch to remain in ground effect but settled briefly back onto the runway before re-establishing flight in ground effect. The instructor stated that the airplane seemed to take longer to accelerate to its best angle of climb speed (Vx), which he attributed to the student’s initial slightly high pitch attitude. When the airplane reached VX, the instructor assumed control of the airplane and maintained airspeed. He stated that the airplane was laboring in its climb, narrowly cleared the trees off the departure end of the runway, and was unable to climb thereafter. Although the engine was running, it was “noticeably weak.” **The instructor raised the flaps** and continued to fly the airplane at Vx and was still not able to climb. He noted that the airplane was about 200 ft above the ground and approaching rising terrain.
> [@](#):
>
> Examination of the data, taking into account the reported surface winds, showed that the airspeed during the final portion of the flight was below Vx but above the listed stall speed from the airplane owner’s manual.
The below I just don’t understand:
> [@](#):
>
> The weather conditions at the departure airport included a temperature of 18°C, and dewpoint of 10°C. According to Federal Aviation Administration Special Airworthiness Information Bulletin CE-09-35, the temperature and dewpoint were in a range of susceptibility for serious icing at glide power and between the range for icing at glide and cruise power and serious icing at cruise power.
Late September in Allentown, a temperature of 18 degrees C (64 F), below 1,000 feet AGL, presents a serious risk of icing? Granted, I learned to fly in Florida; **carb** icing _maybe_, but the text didn’t make it clear. Not sure if this model (-140) is carburated; even if it was, my belief is that carb icing is mostly a concern during low-power (approach, for example) situations.
Given the presence and actions of the instructor, the below shouldn’t be a factor, but including it for completeness:
> [@](#):
>
> Page 8 of 8 CEN22FA436
> Toxicological testing of samples from the student revealed the presence of potentially
> impairing substances; however, according to the flight instructor’s statement, the student had relinquished control of the airplane
The official finding is: “A partial loss of engine power for undetermined reasons.”
From my limited piloting experience, and especially if accompanied by an instructor, if I’m only 200 (or less) feet airborne, which should’ve only taken up a quarter to a third of the runway, and engine/climb performance is concerning, I’m setting 'er back down. But: hindsight and all that.
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### Author:  [@smithsb](https://boards.straightdope.com/u/smithsb)
#### Post date: [June 24, 2024, 6:49pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6256 "2024-06-24T18:49:15Z")
> [@LSLGuy](#):
>
> …And really, really rickety and primitive.
A Cessna 172? Man, moving up from my Aeronca Champ, then to a Cessna 150; a 172 was the Cadillac of the skies. (snerk)
Your perspective moving down and mine moving up are wildly at odds 🙃. No criticism from me; your posts are always enlightening and welcome.
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### Author:  [@Magiver](https://boards.straightdope.com/u/Magiver)
#### Post date: [June 24, 2024, 7:11pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6257 "2024-06-24T19:11:55Z")
“The engine seemed weak” translates to not being able to reach normal power RPM’s. A Cherokee 140 is an easy plane to fly especially with only 2 people in it. And I never experienced carb icing in one.
And I agree with Raza, the instructor should have aborted takeoff if there was runway left. I have experienced an impulse coupler failure on that engine (during run-up) in a different plane. I don’t know why it wouldn’t run on the other mag but the more I fiddled with it the worse it got and that was on the ground.
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### Author:  [@JKellyMap](https://boards.straightdope.com/u/JKellyMap)
#### Post date: [June 24, 2024, 11:39pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6258 "2024-06-24T23:39:28Z")
On Google Maps sat view (or equivalent), look at South Ranchwood Ave.,just SE of the town of Yukon. Where it meets I-344 (in a patch of woods), it looks rather like the runway they were supposed to land on, several miles beyond (and I-344 looks kinda like the longer N-S runway of the airport).
I find this hard to believe as the cause, though, because: 1. The boulevard lacks those special lights at the end of (and extending beyond) any runway; 2. Even under visual flight rules, commercial
pilots (as I understand it) are still supposed to use nav aids (capturing glide slopes, say? Or PAPI lights, at the very least!) to verify their location during approach.
Or no?
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### Author:  [@Magiver](https://boards.straightdope.com/u/Magiver)
#### Post date: [June 25, 2024, 6:30pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6259 "2024-06-25T18:30:29Z")
Yes to all your questions. There are a lot of overlapping indications regarding a proper approach and visual recognition of a runway.
I haven’t seen any information regarding Southwest flight 4069 incident (LAS/OKC 12:05 AM 6/19/24). I would have expected release of tower communications but I’m not good at surfing FAA investigation. All I’ve seen so far was that they were 9 miles out and the tower alerted them to a low altitude situation.
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### Author:  [@Magiver](https://boards.straightdope.com/u/Magiver)
#### Post date: [June 25, 2024, 7:04pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6260 "2024-06-25T19:04:37Z")
Not sure why my post didn’t take so I’m re-posting it.
Yes to all your questions. There are a lot of overlapping indications regarding a proper approach and visual recognition of a runway. But I don’t think they had gotten to that point of the flight.
I haven’t seen much information regarding Southwest flight 4069 incident (LAS/OKC 12:05 AM 6/19/24). All I’ve seen so far was that they were 9 miles out and they were alerted to a low altitude situation.
[The audio](https://audio.com/dale-denwalt/audio/swa4069-approach) I found started with Approach Control contacting the crew about a low altitude issue. They started to climb and were asked if they still wanted runway 13 and they said they would take 17R.
The audio I linked to said it was Approach Control and not the Tower so that implies they weren’t cleared to land or had switched over to Tower to coordinate the landing.
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### Author:  [@JKellyMap](https://boards.straightdope.com/u/JKellyMap)
#### Post date: [June 25, 2024, 11:20pm UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6261 "2024-06-25T23:20:05Z")
Thanks. Very odd, then. Perhaps an altimeter malfunction (unlikely); or perhaps they set the barometric pressure incorrectly on the altimeter (possible, but it would only cause an error of a couple hundred feet, not a thousand).
Perhaps both pilots were distracted trying to troubleshoot some unrelated problem, and neglected to monitor their altitude and/or position? I can think of two fatal accidents over the last 40 years where this was the cause (in both cases, the distraction was about the landing gear).
But precisely because those accidents (and others like them) have drilled into all pilots’ heads the importance of CRM, I doubt this was the issue in this case.
Very odd! I look forward to learning the cause. Probably not “meaty” nor unique enough to merit a MentourPilot video, so I’ll rely on you folks to enlighten me, once more is known.
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### Author:  [@Magiver](https://boards.straightdope.com/u/Magiver)
#### Post date: [June 26, 2024, 12:14am UTC](https://boards.straightdope.com/t/the-great-ongoing-aviation-thread-general-and-other-part-1/600499/6262 "2024-06-26T00:14:15Z")
They could have been distracted. But they perked right up and started to ascend right after Approach contacted them. I hazard a guess that the internal conversation started with “oh shit”.
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