#aerobraking

[jurph]

Coming Back

A little obsessed with re-entry as a concept these days. The idea of a long cold journey that is arduous, but safe, and all that is required is to endure... followed by a few minutes of being baptized in searing white plasma, no radio communications, some outer layer you thought of as "yourself" being excised as an inevitable cost, a mostly-ballistic trajectory.

It's "mostly ballistic": once you pick your lane, once you shoot your shot, you make the last few trim adjustments with your hydrazine-or-whatever thrusters: and now you've placed your bets. There's not really anything you can do on re-entry where adding energy will help, because the fundamental problem is one of shedding energy. The speed that got you through the journey is now a hazard. You have to re-acclimate to moving slowly. You have to come back, adopt a speed that is more favorable to atmosphere and breathing and humanity, and that means aerobraking. Every part of that is basically deterministic though: too steep and the heat builds up too fast and cooks you; you couldn't absorb the change fast enough. Too shallow and the exposure to heat over dozens of minutes wears you down: you didn't rip the band-aid off fast enough, you overshot your target, you spent so long getting back to normal that you left yourself vulnerable.

So every re-entry trajectory is this Goldilocks thing where you come back, talk to some experts on the far end and say "what is the best way to finish this" and trust them. The final exam is setting your course, knuckling down, and coming through the short dark window of loneliness to a place where you can open the parachutes and splash down safely, and wait for someone to pick you up and say "welcome home. you made it."

[professionalchaoticdumbass]

holy fuck i've probably recorded like, 20 gb of jool 5 so far and the laythe landing isn't even finished

[prokopetz]

To be fair, a lot of goofy-sounding rocketry/aerospace terminology has a legitimate nomenclatural role beyond just being silly euphemisms.

"Unplanned rapid disassembly", for example, exists as the necessary counterpart to planned rapid disassembly: sometimes a rocket is legitimately supposed to fall apart or blow up, so you need a specific term to emphasise that it wasn't supposed to do that.

Similarly, "lithobraking" was coined by analogy with aerobraking (shedding velocity via atmospheric friction) and hydrobraking (shedding velocity by landing in water), and it does have some intentional applications; the Mars Pathfinder probe, for example, was deliberately crashed into the Martian surface while surrounded by giant airbags, and reportedly bounced at least 15 times before coming to rest.

(That said, aerospace engineers absolutely do use these terms humorously as well, because engineers are just Like That.)

[lonestarflight]

The Space Shuttle's vertical tail is 27 feet high and 22 feet long at the base. It ensures the stability and the direction of the orbiter in flight. It supports the mobiles elements which are used to oriente the orbiter or to slow down (areobreak). These last ones are jointed with four pieces and controlled by an electrical engine. The box of the vertical stabilizer is made of two strengten pieces mashin-finished from one piece, panels. The box is settled to the rear part of the fuselage by ten bolts. The mobile parts (direction and aerobrake) are made of aluminium alloy and panels in honeycomb structure.

All were built by Fairchild Republic Company, in Long Island, New York.

source

Boeing Images: B1230615

[feybeasts]

Today in flight sim shenanigans: landing at 200+ knots after losing an engine to a Tunguska site, for SOME REASON my aerobraking was only about... half... as effective?

[portent-transportation]

Portent Transport part 3

Luckily, Munar returns are rather efficient. That's why this craft is so small, actually.

And Valentina has plenty of fuel.

But no way to safely reenter Kerbin's atmosphere? No heat shields, not even a parachute?

(Author's note: There is a weird, fudging way to get kerbals to reenter safely on their own, but that's more of a last resort kind of thing)

THAT'S BECAUSE WE DO IT OLDSCHOOL HAHAHAHA

Just kidding. We used an (overzealous) aerobrake that needed a LOT of correction burning. We almost DID do it oldschool by dipping too low into the atmosphere.

But Valentina has another target.

Portent's own return service!

Wait. Hmmm.

Uh oh. Well, that sucks. Looks like there's an incompatibility. The return service vessel is so old that it doesn't even have a miniature docking port.

Valentina is getting home and so is the scientific data, but there's no way to save the fuel she INTENDED to leave behind on the return service outpost.

TECHNICALLY. Technically, the mission was an astounding success.

Few missions involving anything more complex than a landing will proceed without any hitches.

Returning to orbit the wrong way from the surface of Mun, thereby wasting a LOT of fuel to correct it, using fuel from a fuel outpost that doesn't have a resupply ship? Shit happens.

Almost burn up in the atmosphere by decelerating too fast because you're impatient? That's kind of weird, but shit happens.

Forgot that your vessel couldn't dock with the return station, thereby wasting ALL THE REST of the fuel you took with you? I mean, uh... Shit happens?

But forgetting to pack snacks when you're stuck in the mountains because you overshot the sea by a few KM?

Well. That'll leave any veteran astronaut looking completely gormless after surviving a trip to Mun.

Wait.

WHAT DID YOU SAY?

THE KSP OFFERED US WHAT?

Uh,... yeah, ignore that part.

I see great fortune in Portent Transportation's future. And multiple very funny missions.

[jayahult]

Eight

Eight crew-members. This ship is supposed to run with eight crew-members.

That thought kept echoing in my head as I stared out the window towards the inky black, pulling away from the fray. I couldn't look behind me. Allison was behind me. She was behind me. I checked the damage control display again, as if it would make things better. We were running on one of six thrusters remaining. The ECM was spasming, shooting out false signals, eight on our tail, sixteen, one, twenty-five. I hit the switch to try to purge the system. I didn't even want to think that he had an active fusion reactor sitting towards the tail of the ship. I couldn't bring myself to check it again. Levi had patched the leak, the poor bastard. I checked the life-support. The missile had torn open the side of the ship like can-opener. A large portion of the oxygen had gone with our cramped quarters; the carbon recyclers were several miles behind us, alongside our emergency oxygen kits. I punched an approximation of our status into the computer. Levi thumped his foot behind me. We had about twenty hours before we'd all suffocate.

I sighed, and looked back at Allison. She was dead. I had no idea how she got this far. She must have been just getting through the locks when she was exposed to the vacuum. Our suits were designed for helping with rapid decompression, but there was only so much that they could do. Her face was red with blood, her eyes desperate and sad and trapped that way forever. Levi was alive for now. He was near to the reactor. He saw it nearly breach. Fusion reactors don't melt down, not like the old fission systems were prone to, but a leak on a functioning reactor core could and would release massive amounts of radiation. His face was ruddy and sad. He couldn't meet my eyes. He was the oldest among us, twenty-seven.

The radio crackled to life, startling me. I kicked the other chair as I turned around and Allison floated against the chair that I had crudely locked her into, and her dead mouth lolled open as if to speak what was said over the channel:

"Attention, attention, all vessels - retreat has been ordered. Repeat - retreat has been ordered. Repeat -"

I checked the TMCS, and the fuel reserves. Technically we weren't dead in space, but we were as close to it as we could get. We wouldn't make it back to carrier in time for the retreat. That meant capture, or re-entry. By everything I'd heard being taken prisoner by the RTs would make you wish you were dead. We weren't built for re-entry. Even if we got a stable trajectory that wouldn't kill us by lithobraking, there was the problem of shutting down the reactor in time to minimize damage to ourselves and the local environment. The local comms opened up as well.

"Is anyone alive up there?"

It was Silvia. Still alive. She was in the engine room when the breach happened, which means that she'd be cut off from the rest of us.

"We're alive!" I said frantically, "It's Juno and Levi. Seems like we're the only other survivors. Listen, do you have an EVA suit near you? I need you at the bridge. Allison is dead. Levi is-"

I glanced at him.

"He's injured. He's going to need medical attention, but first we need to burn and re-enter Calvin-22-"

"Are you insane?"

"I've already weighed the options, Silvia. We're going to either die in orbit, in aerobrake, in lithobrake or we'll be executed by tribunal by some RTs, or we can take our best chance."

"You are insane," she said, "Thruster three looks like it could still function if I make a quick fix. I'm going to try that and head to you."

"Thank you," I said.

"You're welcome, ma'am."

The comm crackled again, and went silent, and I slumped in the chair, confused. It was only a few moments later that I realized that since Allison was dead, I was the highest-ranking person on the ship left. Levi waited for a moment.

"So, how do you feel about the promotion?"

"What?"

"I- nevermind," he said, "Thought it'd make you laugh. Ma'am, you entered the numbers wrong."

"Hm?"

He reached over to the life support panel, and tapped the backspace lightly before entering three instead of eight. I hadn't even noticed my mistake.

[hazstur]

i'm getting into like perfumes and scents and stuff and i ordered some samples from Fyrinnae and one of them is called 'Aerobraking' and it's exactly what I imagine James T Kirk smells like

[schoolpenin]

January 24th: The Apple Macintosh Launches and Reimagines Personal Computing

1990 – Japan Launches Hiten Lunar Probe: On January 24, 1990, Japan made a significant leap in space exploration by launching its first lunar probe, Hiten. This robotic spacecraft marked Japan’s entry into lunar exploration and executed an aerobraking manoeuvre, showcasing technological advancements in deep space exploration. Impact on Today’s Life: Japan’s continued contributions to space…

[slishthelovemachine]

obsessed w fyrinnae's aerobraking. it's dries down on me to this very..idk powdery false-sweet mixed with the metal pipe clanging sound, motor oil and sniffing rust

[merkabici]

Look 795 una máquina para carreras con un perfil específicamente aerodinámico

La bicicleta tope gama para carretera de Look, el modelo 795, disponible para el catálogo 2016 se ofrecerá hasta en 2 plataformas: La 795 Aerolight que se caracterizará por contar con los frenos frontales integrados en la horquilla y un montaje del freno trasero por debajo de las vainas; mientras que la 795 Light que se ejecuta con un sistema de frenos de pinza tradicional. Detalles de bicicletas completas y precios de la Look 795 Ya entre las opciones de configuración disponibles, se puede obtener una 795 construida alrededor de grupos mecánicos estándar de Shimano y SRAM, y debido a la integración con el freno delantero es que se ha tenido que trabajar con las palancas de Shimano (aunque de igual forma se puede trabajar con piezas de SRAM y Campagnolo –sin embargo, en este preciso instante hay complicaciones con el grupo electrónico Campagnolo EPS debido a la forma dela batería-). Ahora bien, al configurar con un grupo SRAM Red (sin el uso de pedales) se puede obtener una bicicleta completa que puede tener un peso en alrededor de 5.77 kg; una producción que además contaría con el uso de un set de bielas en fibra de carbono de marca propia (unidad Zed2 con peso en alrededor de 320gr). Sin embargo, la 795 no es una opción realmente económica; ya que una opción como la 795 Aerolight con grupo Shimano Ultegra Di2 y set de ruedas Mavic CXR 60 (con peso cercano a los 7.47kg) se ofrece por un estándar de precio cercano a los 12.000 euros para una talla grande. Y si bien, la máquina ya se encontraba lista desde hace un año, debido al pasado clima financiero en Look decidieron aplazar esta situación. Al final, Look puede reclamar que la 795 Aerolight es cerca de 11% más aerodinámica en comparación con su predecesora (la 695 Aerolight), incluyendo toda una gama de características que han sido diseñadas para hacer de este modelo lo más aerodinámico posible. Otros detalles interesantes en la Look 795 En tanto, el cuadro hace uso de perfiles de tubo aerodinámicos NACA (National Advisory Committee for Aeronautics) para mantener gran fluidez del aire. Así, en la Aerolight, Look emplea su sistema de freno delantero Aerobrake 2 que se oculta en la horquilla, en tanto que el freno trasero emplea un sistema Direct Mount de Shimano para colocar en las vainas. Y por el lado de la 795 Light se hace uso de un montaje directo de las pinzas en dónde uno esperaría que estuvieran colocadas. Por otro lado, el manillar compatc es una pieza nueva de parte de la empresa y es el resultado del trabajo en colaboración de corredores francesas pista; proporcionándose una parte superior plana, con formas ergonómicas y caídas de 120mm (con un largo de 75mm). En tanto, la salida de los cables de los frenos y mandos corren por debajo del manillar (con ligera exposición de los cables antes de desaparecer por completo del cuadro). Ya en el interior del cuadro, los cables se guían alrededor del tubo de dirección (una característica que es una de los 11 diseños patentados en esta bicicleta). En relación al diseño de la potencia también se mantiene al ras del tubo superior y no cuenta con separadores hacia el frente, pero la potencia puede ser ajustable entre 13° negativos y 17° positivos. Finalmente, el tubo del sillín reclama proporcionar cerca de 20% de mayor flexibilidad en comparación con la 695, y esto último ha sido posible gracias al uso de diferentes grados de carbono. Mientras que, para mejorar aún más la comodidad, Look ofrece su tija E-Post 2, junto al tubo del sillín que se encuentra separado por un elastómero que ayuda en la absorción de vibraciones (lo que evita que el ciclista se encuentre en contacto directo). Por último, el mecanismo de bloqueo ha sido diseñado para trabajar mediante el giro de un tornillo y la tija se ubica justo al ras del tubo del sillín. Ya en otros detalles del cuadro, la caja del pedalier es mucho más ancha y 30gr más ligera en comparación con la 695. Y el uso de las vainas rectas deben de permitir obtener mayor rigidez en comparación con la 695, pero con un diseño que aún proporciona cierta flexibilidad en superficies rugosas. Para mayor información te invitamos a ingresar al sitio web oficial de Look. Recuerda que en MerKaBici puedes hallar una gran selección de bicicletas para carretera de diferentes marcas, por lo cual te invitamos a consultar las ofertas que son publicadas por tiendas y particulares en modelos de primera y segunda mano. Imágenes de lookcycle.com Read the full article

[remys-rockets]

L1 Certification, Take 1

I began to prepare for a shot at my L1 certification during the off-season at the end of 2021. I was still extremely new to rocketry, only having flown once on a borrowed rocket to get a taste for it.

I decided the best way to do it was with a kit, and so after a pile of reading I settled on an Aerotech HV Arcas. Motor availability issues continue to plague Australia, but I was able to buy a H-something-or-other from a very helpful VRA member. I simmed it in OpenRocket (with my admittedly limited knowledge at the time) to make sure I was good to go.

Assembly was fairly simple, with through-the-wall fins which snapped into place on the inside centring rings. I painted it bright purple and named it CRUNCHWRAP 1, as a tribute to my favourite Taco Bell treat which kept me going throughout the endless lockdowns.

I rolled up to fly with my rocket, my parachute, and apparently not my Aeropack retainer ring. No matter, friction fitting it worked. What didn't work, however, was apparently the delay charge. It had been pre-drilled by the person I bought it off, but that was fine because it matched the ideal delay which OpenRocket had given me for my flight (about 7 seconds).

Liftoff and boost phase went well, with a simulated apogee of about 2800ft... and then it was all downhill from here. Whatever was left of the ejection charge fired, but it wasn't enough to actually separate the rocket. No parachute was deployed, with the rocket tumbling down from apogee rather than descending gracefully under its parachute as intended. Somehow, it managed to a) aerobrake and b) land in mud soft enough that it was undamaged and re-flyable (???). No certification for me that day.

Upon opening it up, I found that the ejection charge had indeed fired, as the chute protector was scorched and smelled like black powder. The rocket had also partially split. Some theories as to what happened:

The charge, although it fired, was damaged somehow when the person whom I bought the motor from had drilled it out

The charge simply wasn't large enough

My pressure bleed hole was too large

I had initially thought that the parachute plus protector may have been packed too tightly and acted as a baffle, but in hindsight that doesn't make sense in this case. That pressure still has to go somewhere.

Anyhow, some small silver linings:

Intact rocket

Construction method proven to be very tough

Time to try again!

L1 Certification, Take 2

A couple weeks later, I managed to source a DMS H135 for a second attempt. I had also loaned my parachute to a friend who unintentionally got it quite crispy, so I made my own. It had identical dimensions to the one which was destroyed, and I used ripstop nylon and nylon builders' line.

This time the boost, coast, and deployment went exactly as planned. What didn't go to plan, however, was recovery. The wind was fairly brisk on the day and the rocket was simulated to about 3000ft. I realised I'd made a mistake in not using a drogue immediately after deployment, and the rocket began to drift far too fast for my liking.

I sadly watched it touch down in the far distance, and set off on my trek to try to recover it. Three hours later, the range was being packed up and I had to call it off. No certification for me that day either.

How to avoid this next time:

Fly a heavier rocket

Use a smaller main chute on a longer delay

Use a chute release device

Use dual-deploy, with a drogue at apogee

Time, once again, to try again!

[shoutasscience-blog]

2001 Mars Odyssey spacecraft by NASA, one of the longest surviving spacecraft

NASA has confirmed that its spacecraft Mars Odyssey one of the longest surviving spacecraft outside the earth has resumed full service following recovery after entering a safe standby mode on Dec. 26, 2016. The Odyssey project team has diagnosed the cause and is restoring the orbiter to full operations

Odyssey launched on Boeing’s Delta II 7925. Courtesy NASA/JPL-Caltech.

History of the 2001 Mars…

[lonestarflight]

“SPACE TRANSPORTATION EVOLUTION”, circa 1981-90.

Shape of things to come.... sadly, it wasn't meant to be.

Top row (L-R): Shuttle II Orbiter, Aerobrake Orbital Transfer Vehicle (AOTV).

The (AOTV) was a two-stage vehicle with a common module and expendable lunar lander.

Middle row (L-R): an unknown shuttle variant, Shuttle-C, unknown, unknown, unknown spaceplane

Eagle Engineering photo: 5312

[rumblyfish]

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Art of my oc Kotose  toyhou.se/146023.kotose-nakamu… Drawn Jan 32, 2014 Here is my tsun oc Kotose. I drew her last year for inktober so it's been a while she's popped up in my gallery ^^ 2017 Commissions + Customs (OPEN)  |  Tumblr | RumCandyAdopt  | Flavors.me | YouTube | Art Amino | RumbyFish @ PaigeeWorld | RumblyFish @ Furaffinity |  Mini Black Velvet @ Gaia Online | Rumby @ Toyhou.se | Rum @ Picarto | Instagram  | Rumby @ GASR |   Art Quest  ♥ patreon Art + Characters © RumbyFishy  /  RumCandyAdopt / @rumblyfish 

[notesbyash]

love learning about bizarre niche academic concepts. one professor at this university is studying something called the "food-energy-water nexus." their colleague is attempting to change satellite orbits by attaching a giant tether to a space probe and using a planet's atmosphere as a frictional aerobrake. another colleague literally specializes in tiny explosions. aerospace is a normal major.