
Boeing has flown the 747-8 to Mach .98, within 7 knots of Mach 1 - jlangenauer
http://www.wired.com/autopia/2011/02/looking-inside-boeings-new-747/
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dotBen
By launching the plane in red rather than blue, Boing clearly sees their
future growth market (for this plane at least) as being the Asian countries
--- where red is the sign of luck and prosperity.

Also, this interested me:

 _The two airlines with orders for the 747-8, Lufthansa and Korean Air, were
in Seattle for the unveiling along with private customers for the of the
business jet version_

A private business jet version of the 747-8 -- the world's longest passenger
jet? I wonder what that looks like inside and who buys them?

~~~
thematt
_Boing clearly sees their future growth market (for this plane at least) as
being the Asian countries_

I just talked to the CEO/President of Boeing the other night and you're
absolutely right, that's exactly what their focus is. Not necessarily focused
on Asia alone, but most of their sales are international now, particularly to
the emerging markets -- and he had no qualms in saying the future of Boeing
was outside the United States.

 _A private business jet version of the 747-8 -- the world's longest passenger
jet? I wonder what that looks like inside and who buys them?_

Saudi Princes and other royalty from the Middle East. Often times when they
land at Boeing field in Seattle they show off and let people come on-board for
tours.

~~~
bl4k
> Saudi Princes and other royalty from the Middle East.

Getting their orders in before their governments fall

We hope

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ghshephard
More interesting in the article was the detail surrounding how Boeing
eliminates "Flutter" with an automatic fly-by-wire modal-suppression with a
'software law' - it commands an outboard aileron to basically counteract the
flutter out of phase and dampen it out.

I couldn't help but think "Autonomic Nervous System" :-)

~~~
icegreentea
Then you'll love every 5th (and many 4th) generation fighter planes. If you
watch a F-22 in straight level flight, you can sometimes see subtle twitches
in the control surfaces. Makes you kinda warm and fuzzy. It's alive!

~~~
bl4k
They wouldn't be able to fly without it - they aren't aero stable

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jacques_chester
In fairness, that record was achieved with maximum thrust while descending.

~~~
JshWright
They weren't going for a record... They were pushing the aircraft _well_
beyond what it will be experiencing during normal flight operations.

It wasn't "Hey, look how fast we can make this thing go." It was "See how far
outside the normal operating envelope we can push this before Bad Things®
start to happen?"

~~~
sokoloff
It's required by certification standards: 14 CFR 25.335(b) states:

(b) Design dive speed, V D. V Dmust be selected so that V C/ M Cis not greater
than 0.8 V D/ M D,or so that the minimum speed margin between V C/ M Cand V D/
M Dis the greater of the following values:

(1) From an initial condition of stabilized flight at V C/ M C,the airplane is
upset, flown for 20 seconds along a flight path 7.5° below the initial path,
and then pulled up at a load factor of 1.5 g (0.5 g acceleration increment).
The speed increase occurring in this maneuver may be calculated if reliable or
conservative aerodynamic data is used. Power as specified in §25.175(b)(1)(iv)
is assumed until the pullup is initiated, at which time power reduction and
the use of pilot controlled drag devices may be assumed;

(2) The minimum speed margin must be enough to provide for atmospheric
variations (such as horizontal gusts, and penetration of jet streams and cold
fronts) and for instrument errors and airframe production variations. These
factors may be considered on a probability basis. The margin at altitude where
MCis limited by compressibility effects must not less than 0.07M unless a
lower margin is determined using a rational analysis that includes the effects
of any automatic systems. In any case, the margin may not be reduced to less
than 0.05M.

Vc is the maximum operating airspeed and Mc is the maximum operating Mach
number. Vd is the dive speed and Md is the dive Mach number. Vc and Mc are
called out in an aircraft's Type Certificate Data Sheet. Vd and Md are usually
not on the TCDS.

So, it's not ham-fisted throttle-jockey joy-riding test pilots, but rather a
certification requirement to demonstrate flutter resistance up to the design
dive speed.

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zck
Look how they test the brakes ([http://www.wired.com/autopia/2011/02/looking-
inside-boeings-...](http://www.wired.com/autopia/2011/02/looking-inside-
boeings-new-747/?utm_term=Farzand+Ali&pid=683)):

>One of the final tests still on the agenda for the 747-8 test pilots is a
maximum braking tests. The pilots will abort a take off at approximately 184
knots (212 mph) and come to a stop by standing on the brakes without using
thrust reverse devices. The brakes must be at their maximum allowable wear at
the time of the test. The brakes are 'pre-worn' a bit in the shop, but most of
the work comes down to the pilots to get them ready for the big day. >"We do
repeated, abusive landings to wear down the brakes," says test pilot Mark
Feuerstein.

They slow down from over two hundred miles an hour by _standing on the
brakes_.

~~~
whatusername
Plenty of cars can do that.

Of course -- I don't think there's too many vehicle's on land with the
momentum of a 747 at 320km/h. And definately not many that can compare on a
momentum:surface friction ratio.

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otto
Without altitude and temperature a Mach number is rather useless. (Depending
on altitude the temperature and pressure changes which has an effect on the
speed of sound.)

Also was this just the Mach experienced at the leading edge?

~~~
Nick_C
>Without altitude and temperature a Mach number is rather useless

Actually, no, it's the most important number. See
<http://womanpilot.com/?p=61> (near the end) for why.

