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Boeing 737 MAX 8 crashes

tomahawk6 said:
Anyone remember the Starfighter or the early problems with the tiltrotor ? Its bad enough seeing military widows but when a passenger jet goes down hundreds die.

Canada's
daftandbarmy said:
... The issues were in two areas.

First, the speeds that the F-104 had to fly for approach and landing very high – much higher than the earlier jets – and went very fast, especially for an inexperienced pilot flying in seriously bad weather.

Second, since the Luftwaffe Starfighters’ had to perform the low-level high-speed attack mission and in those kind of sorties the aircraft was very sensitive to control-input and extremely unforgiving to pilot error.

The result was a horrific number of accidents. In fact 61 German F-104s had crashed, with a loss of 35 pilots by mid-1966

My brother-in-law's flew CF104s back in the day in Baden and had the unfortunate experience of having to "punch out" when the plane decided to stop flying. Originally we built 200 aircraft for the RCAF which were originally designed and flown as interceptors, then as nuclear strike and reconnaissance aircraft (jobs it was suitable for) and then as a conventional ground attack (for which it was not so suitable [or so I'm told - not a pilot/no expertise]). Their accident record is as follows:

There were 110 class A accidents in the 25 years that Canada operated the CF-104 resulting in 37 pilot fatalities. Most of these were in the early part of the program centering on teething problems. Of the 110 class A accidents, 21 were attributed to foreign object damage (14 of which were bird strikes), 14 were due to in-flight engine failures, 6 were as a result of faulty maintenance and 9 involved mid-air collisions. Thirty-two aircraft struck the ground flying at low level in poor weather conditions. Of the 37 fatalities, 4 were clearly attributable to systems failures; all of the others were attributable to some form of pilot inattention.[11]

The accident rate of the CF-104 compares favourably to its predecessor, the F-86 Sabre. In only 12 years of operation the F-86 had 282 class A accidents with a loss of 112 pilots. The Sabre was also a simpler aircraft and was normally flown at higher altitude.[12]

The CF-104 was nicknamed the "Widowmaker" by the press but not by the pilots and crews of the aircraft. David Bashow states on page 92 of his book "I never heard a pilot call it the Widowmaker". Sam Firth is quoted on page 93 in Bashow's book "I have never heard a single person who flew, maintained, controlled, or guarded that aircraft of any force (and that includes the Luftwaffe) call it the Widowmaker". The pilots did refer to it, in jest, as the "Aluminium Death Tube", "The Lawn Dart" and "The Flying Phallus" but generally called it the 104 (one oh four) or the Starfighter.[11]

https://en.wikipedia.org/wiki/Canadair_CF-104_Starfighter

:cheers:
 
FJAG said:
Canada's
My brother-in-law's flew CF104s back in the day in Baden and had the unfortunate experience of having to "punch out" when the plane decided to stop flying. Originally we built 200 aircraft for the RCAF which were originally designed and flown as interceptors, then as nuclear strike and reconnaissance aircraft (jobs it was suitable for) and then as a conventional ground attack (for which it was not so suitable [or so I'm told - not a pilot/no expertise]). Their accident record is as follows:

https://en.wikipedia.org/wiki/Canadair_CF-104_Starfighter

:cheers:

I'm no expert but the wingspan of an F 104 was very small. Compare that to an  A10 purpose built ground support aircraft, or the F 15E model. Far bigger surface area = more control.

Supersonic Max or G2G should be able to explain it to us - small words, short sentences and no red crayons please. ;)
 
daftandbarmy said:
The Horrific Reason Germany's Air Force Called the F-104 Starfighter “Widow Maker”

First, the speeds that the F-104 had to fly for approach and landing very high – much higher than the earlier jets – and went very fast, especially for an inexperienced pilot flying in seriously bad weather.

Second, since the Luftwaffe Starfighters’ had to perform the low-level high-speed attack mission and in those kind of sorties the aircraft was very sensitive to control-input and extremely unforgiving to pilot error.

https://news.yahoo.com/horrific-reason-germanys-air-force-170000823.html

"First" Reminds me of the day I was out jogging on the base and a 104 was making various maneuvers on the approach end of the runway. Quite an unusual thing to see being done with a 104. Met the pilot a few days later and he said something to the effect "Oh I was trying different speeds and approaches to landing."

"Second"  Ref flying low level. There was the time the base commander flew into the steel cable of a construction crane.
 
Apropos of nothing whatsoever, does anyone else remember the 1960s DC Comics revival of the Blackhawks comics which had the team flying in F104s?

Blackhawk-140-p06_900_5ae26eed1696b1.11984817.jpg


:cheers:
 
Hamish Seggie said:
I'm no expert but the wingspan of an F 104 was very small. Compare that to an  A10 purpose built ground support aircraft, or the F 15E model. Far bigger surface area = more control.

Supersonic Max or G2G should be able to explain it to us - small words, short sentences and no red crayons please. ;)

Small words:  the wings are way thinner than most planes.  They are extremely sensitive to changing flight angles at low speeds, and can lose lift rapidly if angle limits are exceeded.  Fly the plane at a third or a quarter of it’s design speed and do that a few hundred feet from the ground instead of up at 50,000 feet...well, you get the idea.

Ironically, the F-104 has a lower wing loading than most current airliners (eg. 105 lbs/sq.ft. versus 130 lbs/sq.ft. for an A320), meaning it’s relatively lighter for the size of its wings...even if those wings look like two sheets of 4x8 plywood. ;) 

Bigger words: The issue is the design/profile of the wing and resultant sensitive behaviour at low speeds.  Unlike other planes’ airfoils that are relatively thicker, with greater curved surfaces that respond well to changing airflow angles, the Starfighter had a design purely optimized for supersonic flight. It is a symmetrical wing profile made up of two extremely shallow arcs of a circle, each arc joined at the leading and trailing edge for a total thickness of 3.4% relative to the distance from front to back of the wing.  The wings were approx 12’ front to back where they attached to the aircraft, so the maximum thickness of the wing was 4-3/4” or about the thickness of your fist (why the landing gear and fuel is in the fuselage, not the wings).  At the wing tip, it is only 2-1/2” at its thickest point.  No matter the size of the control surface, the use of a super-thin, symmetrical supersonic airfoil will necessarily result in poor responsive as sub-sonic speeds due to the significantly compromised aerodynamics of the airfoil section that is designed to make lift with shock waves, but instead must do so with laminar flow-based atmospheric pressure differences based on Bernoulli’s Principle (flow speed vs pressure).

If interested in some basic description of supersonic flow/lift, check out http://processprinciples.com/2012/04/lift-in-supersonic-flight/.  Of note, the different between the airfoil in the diagram and the F-104’s wing is that the oblique shock wave’s pressure gradient is distributed angularly across the curvature, vice a concentrated pressure gradient as the angular transition at the reference wing’s double-diamond shape’d mid-chord.

Regards
G2G
 
If I understand, translated into even simpler terms:  Designed to fly high and fast, not low and slow.
 
In the "Boeing 737s.  Of course 737s" department, the FAA has issued an emergency airworthiness directive.  It says 737s that have been in storage during the pandemic could have their engines suddenly fail. The FAA is ordering inspections after four incidents.  The FAA says it affects 2,000 U.S.-registered 737s which have sat idle for more than a week. The FAA says in-flight failures of BOTH engines "could be linked to periods of inactivity due to the COVID-19 public health emergency."  "...This condition, if not addressed, could result in compressor stalls and dual-engine power loss without the ability to restart, which could result in a forced off-airport landing."

https://rgl.faa.gov/Regulatory_and_Guidance_Library/rgad.nsf/AOCADSearch/EC0E5875B315E9E5862585AE007CD448?OpenDocument


https://twitter.com/petemuntean/status/1286618600091131904
 
dapaterson said:
This condition, if not addressed, could result in compressor stalls and dual-engine power loss without the ability to restart, which could result in a forced off-airport landing."

a.k.a. 'Crash'
 
A WestJet 737-800 had a PAN-PAN on arrival at Deer Lake last Friday, due to a flaps issue.

I am curious how similar many issues we will see as aircraft temporarily removed from service for economic reasons slowly resume operations. (To be clear, I do not know whether this a/c was removed from service or not).

https://simpleflying.com/westjet-737-flapless-landing/
 
dapaterson said:
A WestJet 737-800 had a PAN-PAN on arrival at Deer Lake last Friday, due to a flaps issue.

I am curious how similar many issues we will see as aircraft temporarily removed from service for economic reasons slowly resume operations. (To be clear, I do not know whether this a/c was removed from service or not).

https://simpleflying.com/westjet-737-flapless-landing/
I’m a dumbasss infantry guy. Can’t pilots tell the autopilot to piss off and actually fly the bloody things??
 
Hamish Seggie said:
I’m a dumbasss infantry guy. Can’t pilots tell the autopilot to piss off and actually fly the bloody things??

Without reading the article, that was probably not related to the autopilot; it was likely the flaps not moving to the desired setting.  There are different flap settings, like fully up, takeoff (partially down), and down.  There may be a manoeuvring one in there too.

That being said, a lot of current airline flying is done by the autopilot.  Boeing and Airbus have different views on this (until the MAX at least) - Boeing's philosophy was that the pilot could override everything, while Airbus's philosophy was that the computer could fly better than the pilot.  Depending on the category of landing (determined by the aircraft as well as the runway), some airlines can land completely automatically.
 
Dimsum said:
Without reading the article, that was probably not related to the autopilot; it was likely the flaps not moving to the desired setting.  There are different flap settings, like fully up, takeoff (partially down), and down.  There may be a manoeuvring one in there too.

That being said, a lot of current airline flying is done by the autopilot.  Boeing and Airbus have different views on this (until the MAX at least) - Boeing's philosophy was that the pilot could override everything, while Airbus's philosophy was that the computer could fly better than the pilot.  Depending on the category of landing (determined by the aircraft as well as the runway), some airlines can land completely automatically.

"The Landing" in Airplane (1980)"
https://www.youtube.com/watch?v=l2iIq3zaP6k
 
Hamish Seggie said:
I’m a dumbasss infantry guy. Can’t pilots tell the autopilot to piss off and actually fly the bloody things??

Not always.  Sometimes it takes extra steps to over-ride the autopilot.

In the case of West Jet's recent 737 landing at Deer Lake, the flaps wouldn't extend, so they had to land faster, because the wing area without flaps is smaller and to get the same amount of proper lift, you have to fly faster on approach...approximately 350-370 km/h instead of the regular 250 km/h.

In the earlier cases of the MAX crashes, there is a longitudinal/pitch trim cut-out switch on the lower pedestal console to isolate an uncontrollable trim situation, but neither crew used this mechanical over-ride switch.  The investigations to date indicate a number of factors including potential lack of familiarity by the pilots with the MACS system, as there was relatively little additional information provided by Boeing, relative to other 737 models without the MACS system.  That said, a number of Wester operators have noted that, MACS system installed or not, 737-wide standard procedure for longitudinal trim malfunction would have included pitch trim isolation via the cut-out switches.

Regards
G2G
 
I had the dubious distinction of flying what was probably the Max 8's last flight from Canada to Mexico. The crew played it all very well IMO because they never showed any emotional stress. The passengers didn't know the story on that flight at the time but the crew was fully aware. Later, I spoke to airline crew members who told me they were peeing their pants at the time.
 
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