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Makes me think of the famous "707 Barrel Roll" story from its initial testing: https://www.seattletimes.com/seattle-news/60-years-ago-the-f...

“You know that. Now we know that. But just don’t do it anymore.”

Edit: forgot the barrel roll was on a 707 - not a 747




there's film of Tex Johnston's Dash-80 barrel roll https://www.youtube.com/watch?v=AaA7kPfC5Hk

many years later, Boeing Chief Test Pilot John Cashman stated that just before he piloted the maiden flight of the Boeing 777 on Jun. 12, 1994, his last instructions from then Boeing President Phil Condit were “No rolls”. -- anecdote from https://theaviationgeekclub.com/that-time-tex-johnston-barre...

I wonder why "the suits" at Boeing are so against the barrel rolls? The pilots all agree it's not that big a deal, not dangerous, and anybody watching is going to love it.

this article https://www.straightdope.com/21341407/is-it-possible-to-loop... says that the bigger the plane, the more dangerous because it will roll more slowly, and during parts of the roll particularly 90 degrees off "flat" there is no lift and you're going to be falling.

I'm reminded of the tragic crash of a B-52 illustrating a similar circumstance, and this was the pilot's last flight before retiring https://www.youtube.com/watch?v=E6io8Tjv7xk


A barrel roll is one thing to perform in a transport category jet, it is a ~1G maneuver when performed correctly. A loop is altogether different. My good friend Bernardo Malfitano, https://www.understandingairplanes.com/Bernardo-Malfitano.ht... , when he worked as a Structural Methods & Allowables engineer at Boeing, was also an aerobatics pilot on the side and put on a fantastic brown-bag lunch presentation entitled "Can you loop a 747?" where he demonstrated how he calculated the weight, altitude, airspeed, and configuration points to theoretically loop a 747 while staying within the certified load limits, then did a stepwise simulation of the results. It would theoretically be possible, but it would be very close to the limit of the airplane's capabilities.

Found it - "Aerobatic Capabilities of “Marginally Aerobatic” Airplanes" - scroll down to "The Physics of Aerobatics" and click "Paper", toward the end there is a detailed summary of how a transport jet could just barely do a very ugly loop. https://www.understandingairplanes.com/online.html


“Marginally Aerobatic”

Gotta love the understatement there.


§ 91.303 Aerobatic flight. No person may operate an aircraft in aerobatic flight - (a) Over any congested area of a city, town, or settlement; (b) Over an open air assembly of persons; (c) Within the lateral boundaries of the surface areas of Class B, Class C, Class D, or Class E airspace designated for an airport; (d) Within 4 nautical miles of the center line of any Federal airway; (e) Below an altitude of 1,500 feet above the surface; or (f) When flight visibility is less than 3 statute miles. For the purposes of this section, aerobatic flight means an intentional maneuver involving an abrupt change in an aircraft's attitude, an abnormal attitude, or abnormal acceleration, not necessary for normal flight.


The Dash-80 roll was a 1-G maneuver that didn't strain the airframe at all. Local legend says that single barrel roll was enough to convince an airline industry skeptical of jet aircraft to open their checkbooks. Boeing -- in the person of Tex Johnston -- changed the world that day.


The only thing I can think is that it looks dangerous to casual observers, and that's the furthest thing Boeing and the airlines that purchase from them want potential passengers thinking.


Based on my “flight” experience in MSFS and various other games, you have to start high enough to complete a barrel roll, and you have to have good control surface authority that allows such deep rolls. At some scale it becomes hard to start high enough and finish it quick enough.

It’s not a big deal in a clean F-15C to start a barrel roll, change minds, and add a full right deflection for 1s to recover to a level flight. But in a larger and non-manauver-oriented planes like a 747, you might find out that the aircraft under present circumstances cannot command more pitch or roll rates to transition from a high-speed inverted descent to a desired positive climb situation before the altimeter indication would reach zero or below. The latter was not so fun.

Overall, I think it’s reasonable that “the suits” were not embracing it. The test pilots made their point, the world witnessed it, any further attempts weren’t strictly necessary, and frankly would have been scary.


Thank you for sharing this, I had never seen it even though I knew the story. I love how excited Tex is describing the 707. "We had an airplane that was going to shrink the world by a factor of two." the whole idea drips with 1950s techno-optimism.

The Fairchild B-52 crash isn't really comparable to the 707 roll. That was at a much lower altitude and a far more aggressive maneuver.


Tex Johnston's first flight was in 1925 with the age of 11 on a "barnstormer". At the time where the first flight regulation appeared in the US.

Back then "flight acrobatics" beside showing off the skills of a pilot was the art of "selling" planes/flying and making it popular after all the "Jennies" were sold off (and the pilots laid off) by the government after WWI[0] for essentially pennies: about $200 (~$4.000); production cost initially at $5.000 (~$100.000). Civil aviation "mass-adopted".

So, by selling a 707 with a barrel roll is as old school as it gets.

[0]https://web.archive.org/web/20150324051634/http://www.southe...


Even if intellectually you know it's totally safe, it's still something the plane was not explicitly designed to do and literally will never be used for again. I can understand the "oh my god what are you doing" reaction feeling a lot stronger than "I guess he must know what he's doing".


Thank you - I had never seen it. This is great.


That very plane is on display at the Udvar-Hazy center of the Smithsonian National Air and Space Museum, at Dulles airport. Plane nerds MUST go there!! Incredible place.

[1]: https://en.wikipedia.org/wiki/Steven_F._Udvar-Hazy_Center


Agreed, it's the best museum in the DC area.


Should note that's a 707 that Tex Johnston rolled, not a 747. I'm not aware of any barrel rolls performed in a 747.


It wasn't even a 707, it was a prototype model 367-80.

There were some unusually significant structural differences between the prototype dash 80 and production 707's, for example:

> The 132 in (3,400 mm) wide fuselage of the Dash 80 was large enough for four-abreast (two-plus-two) seating like the Stratocruiser. Answering customers' demands and under Douglas competition, Boeing soon realized this would not provide a viable payload, so it widened the fuselage to 144 in (3,660 mm) to allow five-abreast seating and use of the KC-135's tooling.

https://en.wikipedia.org/wiki/Boeing_367-80

https://en.wikipedia.org/wiki/Boeing_707


It's in the wikipedia article, but just want to call something out: That particular airframe 367-80 is in the Air and Space Udvar-Hazy museum at Dulles. It is gorgeous.

The 747s first airframe is at the Museum of Flight in Seattle, and you can _go inside it_. https://www.museumofflight.org/aircraft/boeing-747-121


Those two pages disagree. Your quote is from https://en.wikipedia.org/wiki/Boeing_707, but https://en.wikipedia.org/wiki/Boeing_367-80 has "The Dash 80 fuselage was wide enough at 132 inches (335 cm) for five-abreast seating; two on one side of the aisle and three on the other. The fuselage diameter for the production KC-135 was widened to 144 inches (366 cm) and Boeing originally hoped to build the 707 fuselage with that width. By the time the Boeing company committed to production, the decision had been made to design the production model 707 as a six-abreast design"


They added 26 centimeters. Just barely enough to fit another person.

Seriously, what were they planning to transport? Pixies?


The aisle width and/or chair clearance probably changed as well. Indeed, if only 26 cm was required to add another seat to each row, there must have been substantial wasted space with four-abreast seating.


FTA: "In his Boeing office, he [Tex] hung a sign that proclaimed, 'One test is worth a thousand opinions.'"

I need that sign. ha


Oh good note lol! I misremembered


youtube video of the barrel roll https://www.youtube.com/watch?v=Ra_khhzuFlE




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