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Ambihelical Hexnut
Aug 5, 2008


Can we all please agree that the word drone is stupid.

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fknlo
Jul 6, 2009




Fun Shoe

EightBit posted:

This is hosed, I'm six months to 32 and I'm sharper than ever. loving ancestors and their stupid 90+ year lifespans

I think(?) it's so you can get 25 years before you're forced to retire.

helno
Jun 19, 2003
hmm now were did I leave that plane

Ambihelical Hexnut posted:

Can we all please agree that the word drone is stupid.

It is incredibly ambiguous.

EightBit
Jan 7, 2006
I spent money on this line of text just to make the "Stupid Newbie" go away.

Ambihelical Hexnut posted:

Can we all please agree that the word drone is stupid.

People using drone to refer to RC aircraft that can't fly out of line of sight is dumb.

Godholio
Aug 28, 2002

Does a bear split in the woods near Zheleznogorsk?


fknlo posted:

I think(?) it's so you can get 25 years before you're forced to retire.

Sadly doesn't take into account previous federal service.

Wingnut Ninja
Jan 11, 2003

Mostly Harmless


ehnus posted:

http://7online.com/479757/

JetBlue locks 'em up to avoid an airplane taxiing across the active at JFK that shouldn't have been.

One thing that caught my eye:

quote:

Airport sources tell Eyewitness News that the FAA has not even begun to install the safety lights - a year overdue.

Is it really the FAA's job to install that stuff? I would have thought it's the responsibility of the airport management, given that the FAA is a regulatory agency, not a contractor.

Sagebrush
Feb 26, 2012





Gravy Boat 2k

quote:

"When they said a collision was inevitable if pilot hadn't braked, I said 'WHAT?!'" adds passenger Krista Hollis.

Psion
Dec 13, 2002



Captain Postal posted:


How crowded do U-H and Smithsonian get on weekends? Are they better done during the week? If I had to choose between U-H, Smithsonian A&S and Natural History over a Fri-Sun, is there one that should be done on the Friday? (24-26 April)

A&S will get crowded as the day goes on. That's just how it is. Go when it opens or at the end of the day if you want minimal crowds, but it'll be crowded.

Udvar-Hazy is much larger and more spacious inside to boot - it can handle much larger crowds so when you go isn't as important as just going at all.

if you want some general advice on minimizing crowds, it's go as soon as it opens, weekday or not. That's going to do way more for you than trying to go on a Tuesday in January to U-H so you can be the first person in the space hangar that entire day getting to experience Discovery all by yourself. I mean, having done that, it's cool and all but don't plan a trip around it


Slo-Tek posted:

The U-H is never crowded uncomfortably, it is a huge building, and it is a pain in the rear end to get to. The Air and Space and Natural History on the mall are always slammed, though weekdays are marginally better, as are evenings an hour before close. If you are uncomfortable with all the sharp-elbowed school groups at Natural History, I'd suggest a breather at the Sackler-Freer Gallery. It is one robber baron's collection of East Asian art, right on the mall, and it is always dead empty. The food at the Native American Museum is pretty good, grilled bison with blueberry reduction was better than the microwaved sysco you expect at museums. You do pay museum prices though. The Botanic Garden is also nice, and bite-sized thing to do for an hour, also on the mall.

I agree with all of this advice. You could also stop in at Hirshhorn and find out if modern art works for you. It's never crowded either. I wish I'd had time for Sackler-Freer, it sounded great.

Psion fucked around with this message at 21:14 on Jan 19, 2015

MrChips
Jun 10, 2005

FLIGHT SAFETY TIP: Fatties out first

Biscuit Hider

Gibfender posted:

I'm really jonesing for another MrChips effortpost of cold warbird development. Just give me one more hit

You will be pleased to know that my effortposting is back on! The celestial nav post will be up within a week, and my Cold War posts will resume by the end of the month!

Psion
Dec 13, 2002



In other news when did Udvar-Hazy get an F-100 Super Sabre? Have they had that for years and I didn't notice?

CroatianAlzheimers
Jun 15, 2009

I can't remember why I'm mad at you...



Psion posted:

In other news when did Udvar-Hazy get an F-100 Super Sabre? Have they had that for years and I didn't notice?

It was there when I was last there in 2013.

Psion
Dec 13, 2002



I last went in 2011 and if I'm looking at my old photos right, the corner with the Helldiver and the Super Sabre was empty at the time, so that makes sense.

I also have some restoration hangar shots of something they had just started in 2011 and then the same thing in 2015 that's looking a lot further along. Cool to compare the two.

I might do a "guess the plane" post with pictures of half-assembled restored planes and see who really knows their aviation. I guessed one of two right myself before looking at the display which tells you what everything is. The other was "I know that's not a ___ but I don't know what it is" and I'm curious how many seconds it will take after I post it for someone to ID it correctly. probably five.

Nebakenezzer
Sep 13, 2005

The Mote in God's Eye



MrChips posted:

You will be pleased to know that my effortposting is back on! The celestial nav post will be up within a week, and my Cold War posts will resume by the end of the month!

I am legitimately excited for this

vessbot
Jun 17, 2005
I don't like you because you're dangerous

Ola posted:

"balls to the wall, face space".

In Bulgarian there's "straight with the feet upward," at the same time a sardonic observation on the backwardness of the human condition and foolhardy attitudes in the undertaking of complex and important tasks.

Nebakenezzer posted:

I am legitimately excited for this

Seconded

vessbot
Jun 17, 2005
I don't like you because you're dangerous

oops

Captain Postal
Sep 16, 2007


Psion posted:

A&S will get crowded as the day goes on. That's just how it is. Go when it opens or at the end of the day if you want minimal crowds, but it'll be crowded.

Udvar-Hazy is much larger and more spacious inside to boot - it can handle much larger crowds so when you go isn't as important as just going at all.

if you want some general advice on minimizing crowds, it's go as soon as it opens, weekday or not. That's going to do way more for you than trying to go on a Tuesday in January to U-H so you can be the first person in the space hangar that entire day getting to experience Discovery all by yourself. I mean, having done that, it's cool and all but don't plan a trip around it


I agree with all of this advice. You could also stop in at Hirshhorn and find out if modern art works for you. It's never crowded either. I wish I'd had time for Sackler-Freer, it sounded great.

Awesome. This is the sort of stuff I need to hear!

I probably won't take pictures because I figure that everything on display has at least a million pictures on the net, and I'd rather experience it with eyes than a view finder. But I do not do crowds well, especially crowds of loud children. Plan to fly into Dulles on the Friday morning and head to U-H, then A&S and maybe Nat Hist over the weekend, and other museums as needed if it gets too crowded or I finish early. But knowing what to prioritize is really helpful.

Captain Postal fucked around with this message at 21:50 on Jan 19, 2015

drgitlin
Jul 25, 2003
WHY DOES EVERYONE IN AUTOMOTIVE INSANITY HATE ME? READ ABOUT IT NOW AT HTTPS://ARSCLOWN.COM/GITHEAD/10 REASONS WHY I AM A PRETENTIOUS TWAT

If you hate crowds of children then going to the two busiest museums in the entire country on a Saturday sounds like punishment.

Psion
Dec 13, 2002



I wouldn't say a Friday or a Sunday would be any better, though. If you don't live in DC, it's basically inevitable you'll be dealing with crowds no matter what. If the plan is to fly into DC on Friday, there's basically zero possible way to get from Dulles into downtown and into your hotel and then into A&S before the hordes arrive.

If I had to pick one or the other, I'd pick U-H without hesitation, but you can do both in a weekend without hating your entire life.

probably.

One last thing - if you do a little pre-trip planning on what exhibits you really want to hit at least you can bail out when the crowds get too nuts and you'll have seen what you wanted to see most. http://airandspace.si.edu/exhibitio...m?location=mall can get you started.



e: http://airandspace.si.edu/exhibitions/transformers/ hahaha

Psion fucked around with this message at 22:13 on Jan 19, 2015

vessbot
Jun 17, 2005
I don't like you because you're dangerous

I had one of my more embarrassing moments at the Smithsonian downtown... I walked in, saw the Sputnik I hanging from the lobby roof, and excitedly asked if it's the real one

fknlo
Jul 6, 2009




Fun Shoe

Look at you rubes with weekends off

I like having my days off during the week for that specific reason. Way less people doing what I want to do. Fishing, riding my bike, going to museums, etc...

two_beer_bishes
Jun 27, 2004


fknlo posted:

Look at you rubes with weekends off

I like having my days off during the week for that specific reason. Way less people doing what I want to do. Fishing, riding my bike, going to museums, etc...

The benefit to 24/7 jobs! I love having days off during the week

vessbot
Jun 17, 2005
I don't like you because you're dangerous

Here, let me spray some more dronechat spray



Part 2, the Airplane

When it comes to maximizing an airplane for climb performance, the benefits of increased thrust and decreased weight are obvious. What's not obvious are the lengths that record-setters might go to achieve both of these optimizations.

Let's start with thrust:

All engines extract energy from fuel by mixing it with air and burning it. The more fuel and air, the more thrust. Throwing in lots of fuel is easy, but it doesn't do a drat bit of good without a proportional amount of air. Squeezing air into the engine is more of a challenge, and was the focal point of the development of supercharging (which itself spanned an arc of breathtaking complexity in WWII, possibly the topic of a future post). However, when you compress a fuel-air charge to a certain level in a gasoline piston engine, you get “detonation” (a.k.a. pinging or knocking to car guys) which is quickly destructive to an engine. Detonation poses a natural limit to power; in other words, the limit is set for you, and all you can do is figure out where it is, decide on a safety margin from it, and then make that the operational limit. (Not really, there are also tweaks to push detonation back, dating all the way back to the Cleveland air races, then obviously exploited in WWII, and pushed to the brink later at Reno)

Jet engines suffer no such limit. The more fuel you run through them, the hotter things get in the burner and turbine sections, and that does decrease the lifespan of the engine (due to thermal loads, blade creep, etc.). But this lifespan decrease is not a hard limit but rather a sliding scale, so the point at which you want to set the limit is arbitrary and based on your relative valuation of thrust output vs. longevity. Needless to say, when national glory was at stake, the valuation was not on longevity and the fuel governors were set for more thrust. (Later, they were reconfigured to stock settings and returned to the fleet.)

Furthermore, like piston engines, the ability to get the most air into a jet engine is not something taken for granted, so compressor and inlet design are major factors. (Nothing was modified here, as far as I know.) Environmental conditions are just as important. Naturally, we want the densest air possible, which exists at low altitudes and cold temperatures. This is why the site was chosen at Grand Forks, North Dakota, and the attempts set for January. The elevation was about 900 feet MSL, and the temperature about 0 degrees Fahrenheit at the surface.

(The inverse of this is why light plane pilots regularly get into trouble in mountainous areas in the summer: https://www.youtube.com/watch?v=OVM3RRd1vf0)

On the weight side of the equation:

- All paint was stripped, as Wingnut Ninja noted. Just like the Space Shuttle External Tank... for the first few launches it was painted, until someone noticed that it's gonna burn up in the atmosphere and fall into the Atlantic, so what's the point? This saved 600 pounds for the Shuttle, I don't know how much it saved for the Streak Eagle. Now it sits at the National USAF Museum in Dayton, with a coat of standard USAF gray paint to protect it from corrosion.



- The radar was removed.

- One of the 3 hydraulic systems was removed

- The speed brake actuator was removed, and the speed brake secured into position

- Same for the flaps (Notice the lack of flaps for the landing in the video)

- I forgot if this is true, but part of the electrical system was maybe also removed.

- Fuel load was of course at a minimum. The airplane was chained in place with slightly more fuel than needed, it was run up to full afterburner, and then released with explosive bolts right as it hit the required fuel amount. Note from the previous diagrams that the thrust-to-weight ratio was slightly lower for the higher record attempts, due to the heavier fuel load.

What's the bottom line of all these performance enhancements? A sea-level thrust-to-weight ratio around 1.5, which allowed it to accelerate vertically. Even in a standard configuration at light weighs, the F-15 had a T/W of slightly more than 1, and was the first fighter to achieve this.

Now we descend further into the rabbit hole of the Streak Eagle's performance. Remember the Ps plots of the F-104 and F-16 from Part 1? The highest we see at sea level is 800. Well for the Streak Eagle, this was (and I forget the exact amount) around 1500-1800! And here's what that means. Recall that Ps is the rate of energy gain. If you hold airspeed constant via pitch, this rate of energy gain translates to a certain climb rate. (Ps = speed x (thrust - drag) / weight.) If you divide out all the units, you get distance over time. Distance over time is of course speed, and it can also represent climb rate. Well, the climb rate that Ps 1500 translates to, is 1500 feet per second. The lowest straight-line speed this can translate to is, well, 1500 feet per second going straight up. And if you convert that to Mach at sea level, you get Mach 1.3. Remember the envelope I posted a few posts after the main Part 1? The speed limit at sea level is Mach 1.2. (The speed limits down low are usually not performance limits, but some sort of heat limit... be it airframe heating, canopy heating, engine inlet temp limit...) Does it bug you that something isn't adding up? Yes, you're right....

Let this sink in for a minute... in the Streak Eagle, you could overspeed the airframe going straight up!

But in reality, this was kind of a moot point, because these are instantaneous conditions at sea level, and as soon as you start climbing, Ps goes down and the speed limit goes up, so the window opens. Nevertheless its still a fact, and was something they still had to be careful about. You have to take a loss somewhere, and the question is what's the least bad way? There are a few solutions:

1. Reduce power or add drag by opening the speed brake. Obviously, this defeats the mission and is stupid.

2. Add drag in a more useful way by doing a max-G pull to the vertical (G's always entail induced drag). This would more quickly aim your flight path upward, which is where you want to go. Once at max Ps, any horizontal motion is wasted. They didn't do this.

3. Pull earlier, and lighter. They did this. They pulled at Mach .65 (whereas max Ps is at Mach .9) and pulled 2.5 G's (max is 9 G's).

2 and 3 are both sensible choices. 2 has the advantage over 3 in going to max Ps, while 3 has the advantage over 2 in pulling less G and therefore inducing less drag, as well as starting to aim the flight path up sooner. More capable minds than mine apparently calculated that 3's advantage outweighed 2's, and therefore flew that profile.

A little history and context. Before the Streak Eagle, some of the records were held by the F-4 Phantom (as flown in Project High Jump by John Young of NASA fame), and others by the MiG-25. Afterward, some records were re-taken by the MiG-25, and others claimed by the P-42, the Streak Eagle's counterpart in the Su-27 program. The F-15 doesn't hold any of them now.



Neat note about the earlier Phantom time-to-climbs. For the low altitude records, they went to where it was cold and the airport was low, for reasons stated previously. But for the high altitude records, they took a completely different tack. They launched from somewhere in the Southwest at a time of year that the jetstream was over them, and blowing strong. They did that in order to use the wind shear between the different altitude layers to extract energy from the atmosphere! This is something called dynamic soaring and is a very cool topic within its own right.

Even neater note about the context:



That's right, it out-climbed Saturn V to 50 thousand feet.

vessbot fucked around with this message at 08:40 on Jan 20, 2015

Captain Postal
Sep 16, 2007


fknlo posted:

Look at you rubes with weekends off

I like having my days off during the week for that specific reason. Way less people doing what I want to do. Fishing, riding my bike, going to museums, etc...

I'm going on the weekend because...

vessbot posted:

Now it sits at the National USAF Museum in Dayton, with a coat of standard USAF gray paint to protect it from corrosion.

...I'm gonna be here during the week

Terrifying Effigies
Oct 22, 2008

Problems look mighty small from 150 miles up.


Captain Postal posted:

Awesome. This is the sort of stuff I need to hear!

I probably won't take pictures because I figure that everything on display has at least a million pictures on the net, and I'd rather experience it with eyes than a view finder. But I do not do crowds well, especially crowds of loud children. Plan to fly into Dulles on the Friday morning and head to U-H, then A&S and maybe Nat Hist over the weekend, and other museums as needed if it gets too crowded or I finish early. But knowing what to prioritize is really helpful.

Nat Hist is hands down the most crowded museum on the National Mall, through a combination of school/tour groups and an extremely cramped interior. I don't think there's ever a time when it isn't packed to the gills. It's got some great stuff, but there really isn't a strategy to seeing it without crowds.

A&S isn't as bad, especially if you go during off hours. It definitely has the original crown jewels of the collection, but I was struck by how limited it was compared to the U-H when I last went there. The U-H simply has way more room to display the aircraft and let you see them in full, whereas A&S stuffs things into corners. If you had to choose between one or the other, U-H definitely beats the A&S hands down.

Psion posted:

I agree with all of this advice. You could also stop in at Hirshhorn and find out if modern art works for you. It's never crowded either. I wish I'd had time for Sackler-Freer, it sounded great.

The Hirshhorn is closed for renovations, they moved a few exhibits over to the National Gallery but they're hard to find.

Another good DC place is the National Portrait Gallery/American Art Museum in the Old Post Office - there's a ton of great across-the-board US History stuff associated with the various portraits, and it's usually pretty empty.


This is literally the single low point of the U-H...they've got a TV on a 30 second loop showing the SR-71 turning into a transformer that you can hear constantly through most of the hanger

Tide
Mar 27, 2010

by FactsAreUseless


vessbot posted:

Here, let me spray some more dronechat spray


That was such a good read, thank you. What I wouldn't give to have the skill and balls it takes to strap myself into one of those jets and push the envelope past it's breaking point

Psion
Dec 13, 2002



Terrifying Effigies posted:


The Hirshhorn is closed for renovations

Unless it was closed this weekend it's open? The art and industry(?) one is closed though. The main reason I even went to Hirshhorn was the part where the building is a giant donut. Turns out there is some neat stuff. Not everything but one exhibit was pretty good.

Really though it shouldn't be hard for Captain Postal to find a crowd free museum: just pick anything that says art

The Locator
Sep 12, 2004

Out here, everything hurts.




Hair Elf

Wingnut Ninja posted:

One thing that caught my eye:


Is it really the FAA's job to install that stuff? I would have thought it's the responsibility of the airport management, given that the FAA is a regulatory agency, not a contractor.

I would think it's up to the airport authority, like most other things, but I'm sure the FAA could mandate it. I was recently at Sky Harbor picking up a family member, and as I got there somewhat early, I wandered up to the top of the parking garage to watch airplanes. One of the things I noticed, because it has been years since I've been there watching airplanes, so it stood out as different - there is a line of red lights that come on at the edge of every runway, across every taxiway, when there is an aircraft on short final, or on a takeoff roll. These lights go off as soon as the aircraft on the runway passes the taxiway. I assume that this is the same system referred to, and I though it was pretty neat.

Based on how consistent it looked from the garage, and the fact that each crossing/taxiway shut off independently as the runway cleared, I assume that it's all automated.

ctishman
Apr 26, 2005

Oh Giraffe you're havin' a laugh!

Delta 777 ATL-NRT makes a fuel dump, emergency landing and hilarious commentary. Seriously, if anything can generate a new thread title, it's this dude's voiceover.
https://www.youtube.com/watch?v=GQB37_9VmNE

Sagebrush
Feb 26, 2012





Gravy Boat 2k

You'd think a planespotter dork like that could recognize two symmetrical streams from mid-wing as a fuel dump.

5 minutes of "WHAT IS THAT SMOKE????"

Previa_fun
Nov 10, 2004

Aww, so I had my slant on. Lay off me!


Dude sounds like a character from "The Californians."

ctishman
Apr 26, 2005

Oh Giraffe you're havin' a laugh!

Sagebrush posted:

You'd think a planespotter dork like that could recognize two symmetrical streams from mid-wing as a fuel dump.

5 minutes of "WHAT IS THAT SMOKE????"

To be fair, he does momentarily postulate that it could be a fuel dump, before immediately reaching the far-more-likely conclusion that it's symmetrical fires near the wing tank fuel vents.

I just wonder how long they had to vent fuel before they were within safe max landing weight. ATL-NRT is NOT a short run.

The Locator
Sep 12, 2004

Out here, everything hurts.




Hair Elf

ctishman posted:

Delta 777 ATL-NRT makes a fuel dump, emergency landing and hilarious commentary. Seriously, if anything can generate a new thread title, it's this dude's voiceover.

Holy crap. I'm kind of a dork, but that guy.. just wow.

Alereon
Feb 6, 2004

Dehumanize yourself and face to Trumpshed

College Slice

ctishman posted:

Delta 777 ATL-NRT makes a fuel dump, emergency landing and hilarious commentary. Seriously, if anything can generate a new thread title, it's this dude's voiceover.
https://www.youtube.com/watch?v=GQB37_9VmNE
"we have no bushile obstruction"

vessbot
Jun 17, 2005
I don't like you because you're dangerous

Sounded like Honey Badger was out spotting.

Ola
Jul 19, 2004



I hope future aviation incidents happen far away from him.

Party Plane Jones
Jul 1, 2007

by Reene


Fun Shoe

vessbot posted:

- All paint was stripped, as Wingnut Ninja noted. Just like the Space Shuttle External Tank... for the first few launches it was painted, until someone noticed that it's gonna burn up in the atmosphere and fall into the Atlantic, so what's the point? This saved 600 pounds for the Shuttle, I don't know how much it saved for the Streak Eagle. Now it sits at the National USAF Museum in Dayton, with a coat of standard USAF gray paint to protect it from corrosion.

From what I remember the weight they saved was around 50 pounds.

Terrifying Effigies
Oct 22, 2008

Problems look mighty small from 150 miles up.


Psion posted:

Unless it was closed this weekend it's open? The art and industry(?) one is closed though. The main reason I even went to Hirshhorn was the part where the building is a giant donut. Turns out there is some neat stuff. Not everything but one exhibit was pretty good.

Really though it shouldn't be hard for Captain Postal to find a crowd free museum: just pick anything that says art

Whoops, was thinking of the Modern Art Gallery building next to the National Gallery.

Inacio
May 20, 2013



What is he SMOKING?
What's going on, 95, you alright?

This loving guy, seriously

Jealous Cow
Apr 4, 2002
I often times speak without thinking

Stop blustering me, wind!

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BIG HEADLINE
Jun 13, 2006

Make your move...'cause mine's gonna be ugly.

Jealous Cow posted:

Stop blustering me, wind!

I made the mistake of reading his "About" page on Youtube:

"Dedicated to aviation related items, arbitrary nonsensical rants, musical interests, smack-talking progressives, severe weather dreams, and anything I find to be ripe for parody. Specifically, govt/political half truths & gorilla dust."

I was not surprised.

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