
FAA Grounds All Cirrus Vision Jets over Angle of Attack Issues - pdx_flyer
https://www.flyingmag.com/faa-grounds-cirrus-vision-jets
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danaliv
Here's the directive:
[http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgad.nsf/...](http://rgl.faa.gov/Regulatory_and_Guidance_Library/rgad.nsf/0/448c46c035e93a6e862583e0007291d8/$FILE/2019-08-51_Emergency.pdf)

This isn't really a grounding, at least not the way the 737 MAX is grounded.
Cirrus jets can't be flown until the AD is complied with, but complying with
the AD is a (relatively) simple matter of replacing the angle of attack
sensors. Once that's done, the aircraft is airworthy again.

The issue is a "quality escape," i.e. the existing sensors weren't built to
spec. There are two screws that attach the vane to the potentiometer; the
factory didn't torque the screws properly and didn't apply thread locker to
them.

So this is a manufacturing error, not a fundamental problem with the design. I
say that just to provide contrast with the MAX issues since the problems are
superficially similar, but quite different once you get into the details.

~~~
AceyMan
Another data point to remind everyone how AoA is one of the most important
metrics wrt flying an airplane (airspeed is right up there, too).

Obligatory citation; imho, one of the webs's great resources—

[https://www.av8n.com/how/htm/aoa.html#sec-aoa-
intro](https://www.av8n.com/how/htm/aoa.html#sec-aoa-intro)

~~~
cjbprime
> everyone how AoA is one of the most important metrics wrt flying an airplane

Pretty difficult argument to make when most planes do not have AoA sensors!

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briandear
Almost all new airplanes have them. The Skyhawk got one as standard equipment
in 2016.

Here’s a thesis on the topic:
[https://kb.osu.edu/bitstream/handle/1811/68634/1/AbramsHonor...](https://kb.osu.edu/bitstream/handle/1811/68634/1/AbramsHonorsThesis.pdf)

~~~
cjbprime
Sure, but almost no-one flies brand new airplanes. What percentage of GA
flights do you guess contain an AoA display? And the argument's supposed to be
that they're a most important indicator for airplanes?

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devy
For those who are annoyed by flyingmag's un-close-able lightbox hovering the
article if you have adblockers installed, here is the content:
[https://outline.com/3zUyc6](https://outline.com/3zUyc6)

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dmitrygr
They did not ground them. They issued an emergency AD (airworthiness
directive). As soon as you comply (replace a sensor) or if you already don't
have a faulty sensor (a specific model number was bad) you may fly

~~~
holtalanm
in light of this information -- i think the headline should be changed within
HN to 'FAA Issues Airworthiness Directive for Cirrus Vision Jets' or something
to that affect.

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pdx_flyer
I just quoted what the article title was. I didn't write the article.

~~~
simcop2387
It's not a dig at you or anything like that. HN likes to try to remove any
kind of editorializing of the article titles regardless of who did it. Though
they usually side on caution with the actual title of the article like you
used.

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ggm
I'm sorry but I read a string of negative messages about the FAA in this.
Firstly, that they know they need to be seen to act more strongly, and
secondly they lack courage: they did it to GA not commercial because they're
scared of the airline lobby.

Why didn't they act like this to commercial aviation?

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exabrial
I was watching a youtube video last weekend of the landing procedures in one
of these jets. The cockpit and avionics are very modern. They automate a ton
of tasks for the pilot and the displays are more "English" than three letter
acronyms.

~~~
outworlder
Good news is, you can spend some money and upgrade any airplane, even a 1950's
Cessna to glass cockpits for a similar experience.

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staunch
Given how absolutely critical sensor data is becoming to aircraft software, it
seems like airplanes should probably have a dozen redundant AoA sensors and
pitot tubes. And the sensors should be of different design and manufacture, so
they're unlikely to all fail under the same conditions.

It seems like the Air France 447 and 737 MAX crashes could have been avoided
just by having highly redundant sensors.

This is probably what will have to happen for fully self-flying aircraft, so
why not do it now with partially self-flying aircraft?

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caprese
Is this exceptional news?

I am curious how often this happens generally

I’ve been told to consider how issues evolve after they stop being reported,
and so I am skeptical whether this is exceptional at all because aircraft
groundings are only in the public interest because of the recent worldwide
coordinated grounding

~~~
dlgeek
Not very.

This is pretty much the same as a standard car recall, just with more
enforcement teeth. FAA says you can't fly until you replace a part that had a
manufacturing defect. Replace it and you're good.

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duxup
That is a strange looking jet with the engine on top angled down...

~~~
zzless
It is absolutely puzzling to me why anybody would prefer this 'jet' to a nice
(used maybe) turboprop like a KingAir or an Aerocommander (heck, even an MU2).
They are (almost) just as fast (or slow), carry more load and do not require a
type rating to fly. Oh, and they cost less and eat about the same amount of
fuel too, ... and are less costly to maintain.

~~~
Stevvo
I think they are designed to appeal to SR20/22 owners looking for an upgrade,
as the only real advantage they offer on the competition is CAPS (although I'd
take the second engine on a kingair over a parachute)

Full glass cockpit is also looks pretty sweet.

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shereadsthenews
To whom is this of interest? How many HN readers are flying around in a $2m
jet, fewer than 100 of which exist.

~~~
PaulAnunda
HN readers who have a general interest in all things aviation.

