
60 years ago: The famous Boeing 707 prototype barrel roll over Lake Washington - Turing_Machine
http://www.seattletimes.com/seattle-news/60-years-ago-the-famous-boeing-707-barrel-roll-over-lake-washington/
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userbinator
Interestingly enough, if the occupants weren't looking outside, a "1G roll"
would feel almost the same as level flight; here's a video showing how
"gravity" seems to invert along with the plane:

[https://www.youtube.com/watch?v=pMWxuKcD6vE](https://www.youtube.com/watch?v=pMWxuKcD6vE)

This is also why pilots can become spatially disoriented:

[https://en.wikipedia.org/wiki/Spatial_disorientation](https://en.wikipedia.org/wiki/Spatial_disorientation)

~~~
mnw21cam
Problem is, it isn't actually a 1G manoeuvre. You can only have a constant 1G
if you are in straight and level flight. If you perform a gentle turn, you
will have very slightly more than 1G as you bank around the turn.

With roll, if you pull positive 1G while inverted, the plane will effectively
be accelerating towards the ground twice as much as if it was in free fall.
When the roll is over, in order to regain straight and level flight, more than
1G must be pulled to counteract the groundwards velocity that has been
accumulated.

~~~
alblue
A descending turn can be done with <1G - it's only a level turn will pull more
than 1G.

~~~
mnw21cam
Yes, you can do a descending turn, with <= 1G. However, you will then come out
of it going down, and unless you want to fly into the cumulogranite you will
need to pull > 1G in order to level out again.

~~~
Retric
If you really want to be pedantic, going east in level flight you are at less
than 1G due to orbital momentum and in vary small part due to altitude. So, in
theory you could do all of this and stay under 1G.

PS: The weight thing can be significant for hypersonic+ aircraft. Also, you
use slightly less fuel going east than west due to earth’s rotation, though
winds are going to be far more important.

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Steko
_What were you doing Tex?

I was selling airplanes._

[https://www.youtube.com/watch?v=Ra_khhzuFlE](https://www.youtube.com/watch?v=Ra_khhzuFlE)

Here's Boeing, doing a 'near vertical' takeoff in the Dreamliner (spoilers:
not really but still impressive), also presumably selling airplanes.

[https://www.youtube.com/watch?v=KYbM-3E11Qo](https://www.youtube.com/watch?v=KYbM-3E11Qo)

~~~
goatforce5
I was at the Farnborough airshow in 1998. Farnborough is one of the largest
commercial/trade airshows in the world. Wikipedia says that $72bn worth of
aircraft were bought at the last show.

The commercial jets are really thrown around at the show. Steep take offs and
really tight banked turns low to the ground so that the aircraft can remain
visible to the people at the airshow.

[https://www.youtube.com/watch?v=T3EgoPDBvLc](https://www.youtube.com/watch?v=T3EgoPDBvLc)

The planes are more than capable of these manoeuvres, but paying passengers
don't want to imagine themselves riding in those planes. Passengers want slow,
steady and graceful flights that wont spill their drinks or upset their
stomachs.

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JacobAldridge
I use this example whenever I'm presenting on the difference between 'Radical'
(High Risk, High Return) and 'Strategic' (Low Risk, High Return) plans. The
difference between the two is Capability - ie, having strategic capability
lowers risk.

This barrel roll, while not a strenuous manoeuvre on the 707, nevertheless
demonstrates confidence in Boeing's manufacturing capability and by executing
it Tex Johnstone convinced plane buyers that purchasing a jet was not a high
risk strategy. "Selling planes" indeed!

~~~
cpncrunch
It's not really a "low risk" maneuver to do an aerobatic maneuver on an
aircraft that isn't certified for it and that doesn't have a g-meter. Ask the
crew of the Lufthansa B720 that crashed trying to do a roll in 1964.

[http://aviation-
safety.net/database/record.php?id=19640715-0](http://aviation-
safety.net/database/record.php?id=19640715-0)

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binarymax
When you hire a pilot with the nickname 'Tex', expect showmanship.

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termain
That aircraft is more properly called the 367-80, or "Dash 80". While it did
serve as the prototype of the 707, its fuselage isn't as wide.

The KC-135 tanker and its derivatives also derive directly from the Dash 80,
rather than the 707. It retains the 80's more narrow fuselage.

~~~
stephengillie
And the article says thus: _It had become Johnston’s job to travel all over
the U.S. to show off the Dash 80, as the 707 was code-named._

~~~
termain
It does, it's just kind of wrong. Things are more interesting than that.

Dash 80 was a nickname for _that particular plane_ , it's model number is
367-80. The 707 is a slightly different aircraft that generally isn't referred
to as a "Dash 80".

The Dash 80 _was_ the prototype for the 707, but strictly speaking, it's model
number isn't 707.

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jlangenauer
It's also claimed, though there's no footage in existence, that a barrel roll
has been performed in a Concorde.

[https://www.youtube.com/watch?v=KYQS3qAIjAo](https://www.youtube.com/watch?v=KYQS3qAIjAo)

~~~
PhantomGremlin
It has to be true. I saw it in a cheezy B movie, surely it wasn't special
effects?

Or maybe it was just a roll, not a barrel roll. I can't remember, it's been
35+ years and I don't want to see the movie again. Anyway, we were expected to
believe that the Concorde is maneuverable enough to evade both a SAM and
missiles from a fighter. My "suspension of disbelief" unfortunately didn't
kick in.
[https://en.wikipedia.org/wiki/The_Concorde_..._Airport_%2779](https://en.wikipedia.org/wiki/The_Concorde_..._Airport_%2779)

Hmmm ... reading the Wiki entry makes me think about wanting to see that movie
again. So many bad disaster films were made in the '70s.

~~~
Gravityloss
If you watch the video Sosuke posted, the Concorde seems surprisingly
maneuverable. Probably since it has a short span so it can roll quickly and a
large amount of thrust.

Actually, the movie used models, you can see the loop scene here:
[https://www.youtube.com/watch?v=Ny_JslCCPxk&feature=youtu.be...](https://www.youtube.com/watch?v=Ny_JslCCPxk&feature=youtu.be&t=46m40s)

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cfj
Technically called an aileron roll.

[https://en.wikipedia.org/wiki/Aileron_roll](https://en.wikipedia.org/wiki/Aileron_roll)

~~~
__rzzzwilson__
No, a barrel roll is different to an aileron roll. The wikipedia article
linked to shows the difference.

A barrel roll requires heading and altitude changes, an aileron roll should
not.

~~~
cpncrunch
Yes, the are different. However what the OP is pointing out is that Tex
actually did an aileron roll and not a barrel roll. (Watch the video and it's
pretty obvious).

~~~
mikeash
I watched the video and it looks like a barrel roll to me. The airplane
doesn't maintain altitude nor heading. Also that engineer who took a photo
while kneeling next to a window would have been on the ceiling at that point
if it had been an aileron roll.

~~~
cpncrunch
If you look at 1:56 on the AviationExplorer video you'll see there is little
or no pitch change, so it couldn't be a barrel roll. I'm not sure how you can
tell that it's heading is changing from that video.

According to wikipedia "An aircraft performing an aileron roll will actually
fly along a slightly helical path, and a very light, positive g force will be
maintained" so the photographer wouldn't have been on the ceiling.

~~~
mikeash
I don't know which AviationExplorer video you're referring to, but there's
supposedly only one video of the maneuver so I assume the one in the article
is the same thing.

I see quite a large pitch change there. The aircraft starts more or less
level, then pulls up. While inverted it begins to move substantially nose
down. As for heading, at the beginning of the video it's pointed well to the
left, and at the end of the maneuver the fuselage is lined up with the camera.

Wikipedia is confused or imprecise. Either that "positive g force" refers to
the force on the aircraft relative to the Earth, or it's just wrong. Reading
through the original reference that statement comes from, I believe it's the
former. The book says:

"...we have managed to substantially increase the angle of attack, to a point
where the inverted wing is capable of maintaining altitude."

If you're maintaining altitude while inverted, you're not pulling positive
gees relative to the airplane, but you _are_ pulling positive gees relative to
the Earth.

You can browse most of the chapter on aileron rolls in the book in question on
Amazon:

[http://www.amazon.com/Basic-Aerobatics-Geza-
Szurovy/dp/00706...](http://www.amazon.com/Basic-Aerobatics-Geza-
Szurovy/dp/0070629269)

~~~
cpncrunch
[https://www.youtube.com/watch?v=AaA7kPfC5Hk](https://www.youtube.com/watch?v=AaA7kPfC5Hk)

See around 1:56. No significant heading or pitch changes that I can see,
although it is difficult to tell because the camera is so far away.

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sosuke
I'm stunned that Bill Allen left behind the photo he was presented with at the
banquet. While he may have not liked it at the time it seems like he never
forgave or recovered from it.

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georgerobinson
Is there anything about the Boeing 707 structurally that makes it possible to
do a barrel roll that would not be possible in later generation jets, such as
the 757, 767, 777 and 787?

~~~
mnw21cam
No. A barrel roll doesn't place much in the way of demands on an airplane's
structure.

~~~
WalterBright
Non-aerobatic airframes are not designed to pull high negative G's. The other
problem with negative G's is the junk that accumulates in the bottom of the
airplane can fall upwards and cause problems.

This is why Tex was careful not to pull negative G's.

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wkcamp
How quickly would the 707 drop in altitude while doing a barrel roll? And did
he need a minimum speed to be able to successfully do it (sort of like an
escape velocity)?

~~~
cmsmith
If it is truly a 1G maneuver, then the answer would be:

    
    
        9.8 m/s^2  *  (1-cos(\theta))
    

Where \theta is the angle off of level flight. So when you are fully inverted,
the plane would be accelerating at 2 G's downward (one to feel like you were
in free-fall inside the cabin, and then one more to push you back into your
seat).

In the film, the roll takes about 12 seconds. A quick numerical integration
shows that by the end of the turn you would be 700m lower than you started,
and have a downward velocity of 120m/s. I'm not a pilot, but I'm sure that the
best practice here would be to start with an upward velocity, and not to
really keep 1G throughout the turn. Those could both lessen your loss of
altitude.

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WalterBright
That picture is one of the two most famous aviation pictures. The other one,
of course, is the 1903 first flight.

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mannykannot
Perhaps inspired by Falk's performance in an Avro Vulcan prototype at the '55
Farnborough, which I think was in July.

[https://www.youtube.com/watch?v=afj19PedlxE](https://www.youtube.com/watch?v=afj19PedlxE)

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inthewoods
Does the size of the plane make executing a roll of this nature challenging?

~~~
strasser
I wouldn't believe so - as Tex explained:

“The airplane does not recognize attitude, providing a maneuver is conducted
at one G. It knows only positive and negative imposed loads and variations in
thrust and drag. The barrel roll is a one G maneuver and quite impressive, but
the airplane never knows it’s inverted.”

As long as you have enough thrust and the plane can withstand the G force, it
will roll.

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tempodox
Is it unreasonable to expect the ability to barrel-roll from any motorised
plane (i.e. not a glider)?

~~~
hn_user2
Any airplane should have no problem--but legally, not allowed unless it is
certified for it.

~~~
bmir-alum-007
Any U.S. pilot caught pulling such maneuvers would be pwned by the FAA. Any
Boeing-employed pilot would be summarily fired as well.

~~~
neurotech1
Boeing sometimes puts some extreme maneuvers into the approved flight test
card, which is performed with FAA approval.

There has been several cases of 737s being rolled (accidentally) without
damaging the airframe.

When test pilots fly extreme maneuvers on an approved test profile, its
usually done at high altitude, not airshow flyover altitude.

Before the famous 787 demo flight, the pilot flew the maneuvers in a
simulator, and did some practice at higher altitude before doing a low
altitude demo routine.

~~~
bmir-alum-007
At Boeing, there's a fine line between selling jets and getting fired. The
last order to Randall Lee Neville from CEO Conners was "no rolls."

------
stefap2
I have a feeling that in today's corporate culture he would be probably fired.

~~~
Zikes
According to the article, he was very nearly fired in 1950s corporate culture.

Regardless of intent or results, pulling an unsanctioned literal stunt with
hardware that represents the majority of your company's assets is going to be
frowned upon.

~~~
lotharbot
some sources say he was fired and then un-fired later in the day, when new
aircraft orders started pouring in.

