Aeronautical Insanity: switching to secondary tolerances

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Platystemon: Feb 13, 2012; BREADS

StandardVC10 posted:

We can still go uglier.

Platystemon fucked around with this message at 03:13 on Oct 31, 2016

# ? Oct 30, 2016 16:19

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# ? Apr 26, 2024 17:41

TheFluff: Dec 13, 2006; FRIENDS, LISTEN TO ME
I AM A SEAGULL
OF WEALTH AND TASTE

I translated a bit from the formerly classified parts of the AJS 37 Viggen flight manual, more specifically the part about recovery from uncontrolled situations. Figured I'd just drop it here in case someone might be interested.

quote:

24.4 Uncontrolled situations
24.4.1 Superstall and spin

If the angle of attack increases above the permitted limits, some yaw disturbances appear around alpha 25-28�, and at alpha 28-30� there are weak pitch-up tendencies. If the stick is moved forward at pitch-up, the aircraft returns to normal alpha, possibly after overshooting up to alpha ~50�. Note that the angle of attack instrument only shows the area -4� to +26�.

If the stick movement forward at the pitch-up is too small or is made too late, so that the angle of attack does not immediately decrease, the aircraft enters superstall or spin.

Superstall is characterized by:
- indicated alpha 26� (really around 60�)
- low rotation speed (< 40�/s)
- stable or oscillating nose attitude

Two types of spin may appear:

Oscillating spin (most common)
- indicated alpha 26� (really around 60�)
- moderate to high rotation speed (> 40�/s)
- moderately to strongly oscillating pitch and/or roll attitude

Flat spin
- indicated alpha 26� (really around 70�)
- high rotation speed (up to 120�/s)
- small or no pitch or roll oscillations

The sink rate in a superstall or spin is around 100 m/s.

If the pitch-up occurs without aileron input, the maneuver usually results in superstall. If the pitch-up occurs with any aileron input active, the aircraft yaws in the opposite direction and the likelihood of a spin increases.

[...]

The oscillating spin may after ≥15 s diverge so that the aircraft rolls inverted, from which position it usually recovers by itself with control surfaces neutral (but see the section on "inverted plunging spiral" below).

In superstall or spin the elevator authority is good, which eases recovery. Aileron input results in adverse yaw, that is to say rolling right gives a yaw to the left and vice versa. Rudder authority is negligible.

Recovery from superstall and oscillating spin is done by moving the stick to a position somewhat forward of the neutral pitch position, with ailerons and rudder neutral.

To recover from a flat spin, the yawing rotation has to be stopped first, which is accomplished with neutral pitch and full roll input in the direction of the rotation (translator's note: "stick into the spin"). When the rotation has just about cased, recovery is done with neutral ailerons and the stick somewhat forward of neutral just like when recovering from superstall and oscillating spin.

If the center of gravity is particularly far to the rear (aircraft with heavy loads on V7 (wing pylons) and no load on S7 (fuselage pylons)) the pitch-up tendency is more pronounced than with normal CoG positions. To return to normal angles of attack a stronger pitch down input is required; the stick must be moved close to its fully forward position.

These properties are not changed to any significant degree by fuselage mounted loads. The properties with both fuselage and underwing loads are not known but are assumed to be the same as with only fuselage loads.

Stalled inverted attitudes have not been possible to achieve in tests. Moving the stick fully forward gives alpha about -30�, there are no pitch-up (pitch-down?) tendencies and when the stick is moved back to neutral the aircraft returns to normal angles of attack.

24.4.2 Plunging spiral
In certain adverse dynamical scenarios the aircraft can enter an uncontrolled attitude of the autorotating type, here called plunging spiral. The plunging spiral, which can be right side up or inverted, is judged to be the potentially most dangerous form of uncontrolled flight that has been discovered during the spin tests of aircraft 37.

24.4.2.1 Inverted plunging spiral
The most common form of the plunging spiral is the inverted one. The following repeatable attitudes/maneuvers result in an inverted plunging spiral:
- Somersault into inverted position from oscillating spin (for example while attempting to recover from a spin with the stick fully forward)
- Stalling the tailfin through so-called "knife flying" (TN: knife edge?)

The inverted plunging spiral is characterized by the following:
- Negative load factor (-1 to -3)
- Low nose
- Rapid rotation around the roll axis (≥ 200�/s)
- High sink rate (≥ 150 m/s)

Moving the stick back and/or aileron input to either side tends to increase the roll rotation speed. The rotation can be stopped by moving the stick fully forward with no aileron input. When the rotation has stopped, the stick is moved back to neutral pitch, and the aircraft is controllable again.

24.4.2.2 Non-inverted plunging spiral
The aircraft only entered a non-inverted plunging spiral on a handful of occasions during the spin tests. It has not been possible to define any repeatable attitude or maneuver that results in a non-inverted plunging spiral.

During the spin tests the non-inverted plunging spiral only occurred on the following two occasions (not repeatable):
- When recovering from an inverted superstall
- When recovering from an oscillating non-inverted spin

The non-inverted plunging spiral is characterized by the following:
- Positive load factor (+1 to +3)
- Low nose
- Rapid rotation around the roll axis (≥ 200�/s)
- High sink rate (≥ 150 m/s)

In a non-inverted plunging spiral, aileron inputs have no effect. Instead, the roll rotation must be stopped by pulling gently back on the stick until the rotation ceases. When the rotation has ceased, the stick is moved forward to the neutral pitch position and the aircraft is controllable again.

Peep the part about the "inverted plunging spiral". Negative G while rotating >200 degrees per sec? :gonk:

# ? Oct 30, 2016 17:45

Saukkis: May 16, 2003; Unless I'm on the inside curve pointing straight at oncoming traffic the high beams stay on and I laugh at your puny protest flashes.
I am Most Important Man. Most Important Man in the World.

Flight testing for fighters must be fun. I imagine you need to put the plane in any possible hosed up situation and then figure out how to recovery. I remember hearing stories about flight testing of some finnish trainer(?) where the plane ended up in flat spin and the only way to recover was for one of the pilots to climb on the wing.

# ? Oct 30, 2016 18:27

HookedOnChthonics: Dec 5, 2015; Profoundly dull

StandardVC10 posted:

We can still go uglier.

That has at least a modicum of weird charisma, plus it cleans up pretty good.

This, on the other hand...

# ? Oct 30, 2016 18:38

MrYenko: Jun 18, 2012; #2 isn't ALWAYS bad...

https://www.thesun.co.uk/news/2077203/ba-pilot-suspended-over-alleged-cockpit-sex-photos-in-stockings-taken-at-38000-feet/ :nws:

Aeronautical Insanity: The last time I took a poo poo at Mach 0.8, my Captain got off.

# ? Oct 30, 2016 20:29

monkeytennis: Apr 26, 2007; Toilet Rascal

MrYenko posted:

https://www.thesun.co.uk/news/2077203/ba-pilot-suspended-over-alleged-cockpit-sex-photos-in-stockings-taken-at-38000-feet/

Aeronautical Insanity: The last time I took a poo poo at Mach 0.8, my Captain got off.

# ? Oct 30, 2016 20:54

Nebakenezzer: Sep 13, 2005; The Mote in God's Eye

[

# ? Oct 30, 2016 23:11

HookedOnChthonics: Dec 5, 2015; Profoundly dull

What's number two there?

I also like that as you get far enough down in google image search results for specific weird-lookin' planes you start getting cross-pollination of others from all the Cracked listicles :v:

vvv I meant in Nebakenezzer's post, haha. This one.

HookedOnChthonics fucked around with this message at 00:57 on Oct 31, 2016

# ? Oct 31, 2016 00:39

BIG HEADLINE: Jun 13, 2006; "Stand back, Ottawan ruffian, or face my lumens!"

HookedOnChthonics posted:

What's number two there?

https://en.wikipedia.org/wiki/Douglas_F4D_Skyray

This planned update was actually a beautiful plane: https://en.wikipedia.org/wiki/Douglas_F5D_Skylancer

BIG HEADLINE fucked around with this message at 00:57 on Oct 31, 2016

# ? Oct 31, 2016 00:53

marumaru: May 20, 2013

http://i.imgur.com/6t5qzhk.gifv

:stare:

# ? Oct 31, 2016 01:07

HookedOnChthonics: Dec 5, 2015; Profoundly dull

^^^
I remember reading a fairly insane account of an evacuation under hostile fire in an HH-43 Huskie; possibly in the context of South American political strife? I think it was in the Time-Life Epic of Flight volume on helicopters; anyone here know more?

BIG HEADLINE posted:

https://en.wikipedia.org/wiki/Douglas_F4D_Skyray

This planned update was actually a beautiful plane: https://en.wikipedia.org/wiki/Douglas_F5D_Skylancer

Oh, I don't even think the Skyray is ugly, more... distinctive, and very unintimidating. It's a wing shape that looks most natural in styrofoam.

Hell I didn't even post the more typical shot of the Thunderceptor cause it's that schnozz on the radar version that's objectionable, not the goofy wing IMO.

HookedOnChthonics fucked around with this message at 01:18 on Oct 31, 2016

# ? Oct 31, 2016 01:07

Alpine Mustache: Jul 11, 2000

Inacio posted:

http://i.imgur.com/6t5qzhk.gifv

I feel drunk watching this

# ? Oct 31, 2016 01:21

Suicide Watch: Sep 8, 2009

HookedOnChthonics posted:

^^^
I remember reading a fairly insane account of an evacuation under hostile fire in an HH-43 Huskie; possibly in the context of South American political strife? I think it was in the Time-Life Epic of Flight volume on helicopters; anyone here know more?

Oh, I don't even think the Skyray is ugly, more... distinctive, and very unintimidating. It's a wing shape that looks most natural in styrofoam.

Hell I didn't even post the more typical shot of the Thunderceptor cause it's that schnozz on the radar version that's objectionable, not the goofy wing IMO.

Was probably the MoH citation for this guy https://en.wikipedia.org/wiki/William_H._Pitsenbarger

# ? Oct 31, 2016 01:36

Nebakenezzer: Sep 13, 2005; The Mote in God's Eye

HookedOnChthonics posted:

vvv I meant in Nebakenezzer's post, haha. This one.

It's a prototype Soviet carrier based turboprop attack aircraft aircraft, the Tupolev-91. Then it was a land based ground attack aircraft when the Soviets decided against carriers. Then it was nothing but ugly, because Khruschev didn't like it.

# ? Oct 31, 2016 01:55

HookedOnChthonics: Dec 5, 2015; Profoundly dull

Suicide Watch posted:

Was probably the MoH citation for this guy https://en.wikipedia.org/wiki/William_H._Pitsenbarger

Hmm, no, the story I'm thinking of was specifically about the difficulty and stress of approaching a landed intermeshed-rotor helicopter while also worrying about ducking bullets, and IIRC there was a civilian VIP involved; some form of ousted politician.

# ? Oct 31, 2016 02:45

aphid_licker: Jan 7, 2009

Nebakenezzer posted:

[

These are basically the aircraft designer equivalent of cutting yourself.

# ? Oct 31, 2016 03:19

Sam Hall: Jun 29, 2003

S.E.2410 Grognard: a goofy-rear end plane even by SNCASE standards.

I mean I kind of like the shape and proportions of the wing at least, but yeah that's 2 jet engines stacked on top of each other English Electric Lightning style, except unlike the Lightning they were big fat centrifugal Rolls Royce Nenes. Nobody designs awkward looking planes quite like the French.

# ? Oct 31, 2016 05:03

~Coxy: Dec 9, 2003; R.I.P. Inter-OS Sass - b.2000AD d.2003AD

slidebite posted:

Wow the news agencies are clamouring for permission to use his video

Weird, I thought they all had agreements in place with Facebook/Twitter/Youtube to get sub-licensee access to them directly.

# ? Oct 31, 2016 07:41

Platystemon: Feb 13, 2012; BREADS

http://i.imgur.com/Va5AGfw.gifv

# ? Oct 31, 2016 14:03

marumaru: May 20, 2013

Platystemon posted:

http://i.imgur.com/Va5AGfw.gifv

"haha loving idiots they think this stupid sign will stop me from getting the SICKEST instagram video eveee- FUUUCKK AAHHHH"

:downs:

# ? Oct 31, 2016 14:30

PT6A: Jan 5, 2006; Public school teachers are callous dictators who won't lift a finger to stop children from peeing in my plane

Wasn't yesterday the last flight of the 747 into SXM? End of an era...

# ? Oct 31, 2016 14:47

Dr_Strangelove: Dec 16, 2003; Mein Fuhrer! THEY WON!

Lavochkin La-200

# ? Oct 31, 2016 14:55

SeaborneClink: Aug 27, 2010; MAWP... MAWP!

PT6A posted:

Wasn't yesterday the last flight of the 747 into SXM? End of an era...

Friday, but yes. Now scheduled 3x/WK A330, with a routing update of AMS-SXM-AMS instead of the intermediate stop at Curacao, which will now be served by a direct flight from AMS on the same 744.

# ? Oct 31, 2016 15:05

ehnus: Apr 16, 2003; Now you're thinking with portals!

Cathay just flew their last passenger 747 flight -- HKG to LAX to drop the kids off before heading to Victorville. End of an era

# ? Oct 31, 2016 15:35

mlmp08: Jul 11, 2004; Prepare for my priapic projectile's exalted penetration; Nap Ghost

Dr_Strangelove posted:

Lavochkin La-200

Early Russian jets are boss as gently caress. Yak-15 is so cute and derpy.

# ? Oct 31, 2016 15:49

Dr_Strangelove: Dec 16, 2003; Mein Fuhrer! THEY WON!

mlmp08 posted:

Early Russian jets are boss as gently caress. Yak-15 is so cute and derpy.

MiG I-320

# ? Oct 31, 2016 17:33

bloops: Dec 31, 2010; Thanks Ape Pussy!

Dr_Strangelove posted:

MiG I-320

This jet is the physical embodiment of a very loud, drawn out sigh.

# ? Oct 31, 2016 19:13

xergm: Sep 8, 2009; The Moon is for Sissies!

Dr_Strangelove posted:

MiG I-320

The shape of the nose cone makes it looks like it should have a propeller and the intake below it would be for passive engine cooling.

I wonder how much the pilot can see, that cockpit is barely over the fuselage.

# ? Oct 31, 2016 19:40

Ola: Jul 19, 2004

Dr_Strangelove posted:

MiG I-320

# ? Oct 31, 2016 20:05

Fredrick: Jan 20, 2008; BRU HU HA HA HA

I've noticed that a lot of Warsaw Pact helicopter-mounted rocket pods, like S-5, are very streamlined, with obvious effort put into reducing their drag. Only their lightest pods seem to be the "giant tin can full of rockets" shape we associate with Hydra launchers.

Is that just the US writing off the drag reduction as not worth the weight savings? Did Russia have a different mission profile for their unguided rocket pods than the US did? Is it because they wanted to stick them on supersonic things, whereas the US didn't? :confused:

# ? Oct 31, 2016 20:19

my kinda ape: Sep 15, 2008; Everything's gonna be A-OK; Oven Wrangler

xergm posted:

The shape of the nose cone makes it looks like it should have a propeller and the intake below it would be for passive engine cooling.

I wonder how much the pilot can see, that cockpit is barely over the fuselage.

Apparently the cockpit actually seats two people side by side!

# ? Oct 31, 2016 20:33

SeaborneClink: Aug 27, 2010; MAWP... MAWP!

Dr_Strangelove posted:

MiG I-320

# ? Oct 31, 2016 21:26

Phy: Jun 27, 2008; Fun Shoe

Inacio posted:

http://i.imgur.com/6t5qzhk.gifv

So I just found out that Anton Flettner, designer of the Flettner Kolibri, the world's first proper production helicopter and also a synchropter, was Paperclipped after the war and ended up as design chief at... Kaman helicopters.

So, that explains why Kaman.

Also Flettner's wife was Jewish, and Himmler apparently shipped her off to Sweden for the duration of the war.

Phy fucked around with this message at 22:56 on Oct 31, 2016

# ? Oct 31, 2016 22:45

priznat: Jul 7, 2009; Let's get drunk and kiss each other all night.

https://twitter.com/heathwblack/status/793198797044064256

# ? Nov 1, 2016 04:54

Godholio: Aug 28, 2002; Does a bear split in the woods near Zheleznogorsk?

Ugh, I bet she gets fired for that.

# ? Nov 1, 2016 04:55

marumaru: May 20, 2013

# ? Nov 1, 2016 14:17

MikeCrotch: Nov 5, 2011; I AM UNJUSTIFIABLY PROUD OF MY SPAGHETTI BOLOGNESE RECIPE

YES, IT IS AN INCREDIBLY SIMPLE DISH

NO, IT IS NOT NORMAL TO USE A PEPPERAMI INSTEAD OF MINCED MEAT

YES, THERE IS TOO MUCH SALT IN MY RECIPE

NO, I WON'T STOP SHARING IT

more like BOLLOCKnese

Whole lotta talk about ugly planes that aren't the Nimrod AWACS :britain:

Fredrick posted:

I've noticed that a lot of Warsaw Pact helicopter-mounted rocket pods, like S-5, are very streamlined, with obvious effort put into reducing their drag. Only their lightest pods seem to be the "giant tin can full of rockets" shape we associate with Hydra launchers.

Is that just the US writing off the drag reduction as not worth the weight savings? Did Russia have a different mission profile for their unguided rocket pods than the US did? Is it because they wanted to stick them on supersonic things, whereas the US didn't?

I would imagine it's because Hinds and other Russian helicopters are much more designed for speed than say, the Apache, so streamlining the rocket pods probably make more sense.

# ? Nov 1, 2016 14:33