Interesting Article with Photos about 1959 707 Crash in Washington State

[tdracer]

This is a rather good article about the only commercial jetliner crash in Washington State. A brand new Braniff on a pre-delivery flight test - Braniff pilot did such a violent Dutch Roll maneuver that it ripped off three of the four engines.
Rare photos of Washington state’s only jetliner crash - MyNorthwest.com (https://mynorthwest.com/3678147/rare-photos-of-evergreen-states-only-jetliner-crash/)

[Flugzeug A]

Thanks td’.

[megan]

Accident report, thanks td, the early days learning there be snakes behind those rocks. We owe the pioneers much.

https://www.baaa-acro.com/sites/default/files/import/uploads/2017/10/N7071.pdf

[treadigraph]

I read somewhere that this Lufthansa B720 crash was thought to have been caused by Dutch roll training, though the rolls could have been intentional.

https://aviation-safety.net/database/record.php?id=19640715-0

[tdracer]

Back when I first joined Boeing (1977), this accident was well known and discussed among the engineering ranks with us newbies.
Reportedly, knowing they were going to crash, the four survivors moved to the tail of the aircraft since that would be the safest place to be when they hit the ground. It does however beg the question why they had four people still in the flight deck - while the aircraft was certainly very difficult to control, I don't see how those not in the pilot's seats could have helped much.

[megan]

Dutch roll is still with us, USAF lost a KC-135 in 2013 where the roll caused the aircraft to lose its tail.

https://www.af.mil/News/Article-Display/Article/473716/investigation-board-determines-cause-of-kc-135-crash-in-may/

treaders, the following suggests they had done one barrel roll, perhaps emulating "Tex" and his demonstration at the boat race, then lost it while attempting the second. The history of the pilot, Werner Baake, may explain his confidence.

https://en.wikipedia.org/wiki/Werner_Baake

[MarkerInbound]

Several of the pilots who did my initial 727 training in the mid 90s were old Braniff pilots. They mentioned this accident and gave a lot of emphasis to Dutch Roll.

[punkalouver]

treaders, the following suggests they had done one barrel roll, perhaps emulating "Tex" and his demonstration at the boat race, then lost it while attempting the second. The history of the pilot, Werner Baake, may explain his confidence.

https://en.wikipedia.org/wiki/Werner_Baake
Does anybody have details of why the second barrel roll was unsuccessful. The first one worked out.

[Prop swinger]

I would imagine that the only people who knew didn't have a chance to pass on their knowledge.

[treadigraph]

treaders, the following suggests they had done one barrel roll, perhaps emulating "Tex" and his demonstration at the boat race, then lost it while attempting the second. The history of the pilot, Werner Baake, may explain his confidence.

Thanks Megan! My recollection is the narrative ended something along the liners of "...though there was nothing to suggest the rolls weren't intentional". It also detailed the Braniff crash. This was Lufthansa's second 720 crash, the first dived into the ground during crew training with no cause identified...

[punkalouver]

I would imagine that the only people who knew didn't have a chance to pass on their knowledge.

Perhaps there was an FDR installed. Same question……Does anybody know why the second barrel roll was unsuccessful?

[fdr]

Perhaps there was an FDR installed. Same question……Does anybody know why the second barrel roll was unsuccessful?

If you can drag out any wreckage pattern, then that may be able to be answered. Without that, there is only an overall expectation that doing aerobatics is better in a Pitts or Bucker than a B720. The Boeings have thrown engines off all over the place from high roll rates, tails don't like high yaw with any Q, and the whole bucket of parts tends to kit-set if you drive it into the ground having fallen out of the whiffer dill from stalling out. Doing aerobatics with a plane that has roll spoilers needs some thinkerising and tummy contemplation before assuming it is the same as a Spad.

Were the engines near the big divot?
Was all of the empennage at the whole?
etc...

There is a fair bit of force developed on the tails of these plains... a whoopsie leading to wiggling alternating control inputs can upset the paint pronto, most of the aircraft doesn't like torsion-bending in large quantities in loud volume settings.The design engineers prefer that drivers avoid messing with their calculations.

[megan]

Does anybody have details of why the second barrel roll was unsuccessful. The first one worked outThere seems to be no definitive explanation as to whether it was a barrel roll or Dutch roll, all conjecture so it seems.

[Pip_Pip]

There seems to be no definitive explanation as to whether it was a barrel roll or Dutch roll
This brings to mind a comment I saw posted underneath a YouTube video on the effect:

"I'm Dutch, I can confirm, this is how we roll."

[punkalouver]

There seems to be no definitive explanation as to whether it was a barrel roll or Dutch roll, all conjecture so it seems.
I have heard about this accident previously. If I remember correctly, the first roll attempt was successful.

I was just curious if someone knowledgeable about the incident had some inside info such as......ex wwII fighter pilot demonstrated a roll successfully then let the copilot try it but but messed it up and was unsuccessful. The description on aviation-safety.net is that it did a complete roll followed by a second unsuccessful roll.

​​​​​I suppose there is an old report somewhere.

Perhaps TDracer has been into Boeing's accident report archives.

Dutch roll is still with us, USAF lost a KC-135 in 2013 where the roll caused the aircraft to lose its tail.

https://www.af.mil/News/Article-Display/Article/473716/investigation-board-determines-cause-of-kc-135-crash-in-may/


There is a YouTube video on the KC135 crash. But it doesn't show the large yaw involved near the end. The side loads on the fin appear to be what damages the structure in such a situation.

[megan]

it doesn't show the large yaw involved near the end. The side loads on the fin appear to be what damages the structure in such a situation"Tex" Johnston the 135/707 test pilot stated that if you allowed the side slip to reach 15° or more you will have lost control, we had a local military 707 doing asymmetric practice, went into a spin when the side slip became too great, flung off a number of engines, hit the ocean otherwise intact. Saw the aircraft fly over the house some 5 minutes before the accident and later observed it lying on the sea bed.

[akaSylvia]

The af.mil site doesn't have much information on the KC-135 roll in 2013 and the link to the report released under FOIA doesn't wexist. In fact, the entire site now seems to have circular links and the Reading Room of released information finds nothing even on the broadest of searches. Frustrating, as I'd love to read the original report on that.

[punkalouver]

"Tex" Johnston the 135/707 test pilot stated that if you allowed the side slip to reach 15° or more you will have lost control, we had a local military 707 doing asymmetric practice, went into a spin when the side slip became too great, flung off a number of engines, hit the ocean otherwise intact. Saw the aircraft fly over the house some 5 minutes before the accident and later observed it lying on the sea bed.
Thanks for the interesting info.

I do wonder if that is a separate lower speed VMC issue where asymmetric thrust resulted in a loss of directional control due to rudder authority capability being exceeded but fin structurally sound versus a higher speed Dutch Roll situation where aerodynamics creates yaw exceeding the fin structural capability. Either of which could lead to a result of yawing forces exceeding engine structural limits.

[megan]

punka, the local accident I mentioned the crew were doing asymmetric as I said, probably what saved the fin coming off perhaps is that they had the rudder boost turned off so were unable to get enough rudder in to control the yaw with two engines on one side at idle. From Aviation Safety,The Board of Inquiry concluded that the instructor devised a demonstration of asymmetric flight that was 'inherently dangerous and that was certain to lead to a sudden departure from controlled flight' and that he did not appreciate this. The Board noted there were deficiencies in the acquisition and documentation of 707 operational knowledge within the RAAF combined with the absence of effective mechanisms to prevent the erosion of operational knowledge at a time when large numbers of pilots were resigning from the air force. There was no official 707 QFI conversion course and associated syllabus and no adequate QFI instructors' manual. There were deficiencies in the documented procedures and limitations pertaining to asymmetric flight in the 707 and a lack of fidelity in the RAAF 707 simulator in the flight regime in which the accident occurred, which, assuming such a requirement existed, required actual practise in flight. 'The captain acted with the best of intentions but without sufficient professional knowledge or understanding of the consequences of the situation in which he placed the aircraft,' the Board said.

[megan]

For those interested in the official report on the KC-135 dutch roll accident here it is, you wish answered akaSylvia,

https://www.baaa-acro.com/sites/default/files/2021-09/63-8877.pdf

[akaSylvia]

Thank you megan !

[punkalouver]

punka, the local accident I mentioned the crew were doing asymmetric as I said, probably what saved the fin coming off perhaps is that they had the rudder boost turned off so were unable to get enough rudder in to control the yaw with two engines on one side at idle. From Aviation Safety,

Thanks for the interesting accident info.

Not sure what speed they were at and what speed their maneuvering speed would have been. If below Va, I believe that the fin can withstand a single full deflection input of the rudder. I suspect this was an accident exacerbated by a lack of sufficient airspeed for the situation they were in.