Questions tagged [aerodynamics]

the effect on a spacecraft of moving through atmosphere, how its density, pressure, temperature, flow velocity, and viscosity affect a craft, and how lift and drag can be used to modify that.

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7
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3answers
167 views

Might Ingenuity tip over?

While Ingenuity patiently waits for its preflight checks to pass, how likely is it that a wind gust could tip it over? How strong and how rare a gust? Those rotors have plenty of area. (Surely NASA ...
2
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1answer
95 views

How do grid fins actually work? Which aerodynamic mechanism(s) produce the torque on the spacecraft?

I’m trying to model the steering force that grid fins exert on a falcon 9. I know these things are not just grid-shaped fins but actually grids of fins. And each of those fins will experience drag and ...
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0answers
119 views

How heavy were Perseverance's balance masses?

Perseverance ejected two 70 kg "cruise balance masses" just before it became an airplane, to move its center of mass off axis and increase its angle of attack from 0° to about 16° to make it ...
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2answers
144 views

Using lasers to reach the Karman line

I've just seen this Anton Petrov video: New Type of Laser Levitation Could Help Us Explore the Mesosphere. It's about this new form of levitation that uses lasers to heat up the air underneath a craft,...
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0answers
52 views

During space shuttle reentry, why was the sign of GALR based on mach number rather than directly on alpha?

(My apologies if this should go in Aviation.SE instead - I'm not quite certain where questions regarding the behaviour of the shuttle's flight controls during reentry should go.) For flight in ...
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0answers
80 views

Why are fins located on stage 2 of Iranian rocket Zol Janah?

Iranian launch vehicle Zol-Janah has fin like structure on the second stage of the vehicle. Does aerodynamic characteristics of vehicle improve with fins near the centre of mass? Also will the fins ...
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1answer
70 views

What is Direct Simulation Monte Carlo and why is it a good method for simulating spacecraft drag in VLEO?

Reducing spacecraft drag in Very Low Earth Orbit through shape optimisation J. A. Walsh and L. Berthoud (2017) show simulations calculating drag coefficients for different "nose cone" shapes ...
3
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0answers
56 views

How large can heatshield holes be?

The tiles on the underside of the STS Orbiter had gaps between them to allow for the frame underneath to shift slightly. However, if the gaps were too large fillers were used. What controls the ...
3
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1answer
174 views

How did the Space Shuttle prevent flying up when reentering the atmosphere?

Always when reentering the atmosphere, the shuttle was pitched up, right? When gliding through the mesosphere, how was it that it didn't fly up again then? Was it due to a certain distribution of ...
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3answers
194 views

How to make a model rocket that doesn't spin?

I'm attempting to build a rocket with 8 fins (four on bottom and four smaller ones towards the top). The four fins near to the top will be attached to servo motors and programmed to stabilize or guide ...
2
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2answers
242 views

Can the Space Shuttle land on Mars assuming there is a paved surface for landing?

Can the Space Shuttle land on Mars if it had a paved runway? Can the Space Shuttle use aerobraking and will its control surfaces provide attitude control? Can the parachute and braking systems stop ...
6
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1answer
69 views

What benefit do the aerodynamic stabilization “pods” on the PSLV-CA provide?

Whilst writing this answer about the PSLV, on this informative page about its Secondary Injection Thrust Vector Control system, this image (cropped) is displayed, showing that for the Core Alone ...
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1answer
786 views

What is the terminal velocity of SpaceX Starship?

What is the terminal velocity of starship on earth and mars during descent? Has SpaceX revealed or hinted the values of projected surface area and drag coefficient of the vehicle?
15
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1answer
779 views

Is Starship aerodynamically stable when travelling nose first?

Is Starship aerodynamically stable when traveling nose first, or does it require constant gimbaling from the main engines to keep it pointing nose first? Is this part of the explanation for why Space ...
4
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3answers
91 views

Changes in Orbital Parameters Due to Drag

Other than STK, are there any commercially software packages available to model changes in orbital parameters due to increases/decreases in satellite drag. I am trying to figure out if aerodynamic ...
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0answers
64 views

Seeking Book about Aerodynamic Design of the Space Shuttle

a few years ago I found a book written by an engineer working on the aerodynamics of the shuttle during design, ALT, and early STS. I have since forgotten the title and author's name. Does that ...
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0answers
102 views

What was the leeward surface temperature of the Apollo Command Module during reentry?

From the Apollo Experience Report: Thermal Protection System, there is a diagram that shows the surface temperatures of the Command Module at various points (image was obtained from this answer). It ...
2
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0answers
110 views

Which deorbit trajectory minimizes reentry heating?

Atmospheric reentry, as I understand it, is a balancing act between minimizing delta-v needed and not burning up or breaking up in the atmosphere. The higher the velocity on reentry, the greater the ...
6
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3answers
1k views

Is there a mathematical formula to calculate drag force without empirical testing?

Typically people put the interested rocket prototype in a wind tunnel to find out the drag force and use the drag force equation to calculate the drag coefficient of the rocket model. I am wondering ...
2
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2answers
174 views

Is aerodynamic control in an exosphere possible, in case velocity is high enough?

Exospheres are different than the lower parts of atmospheres (if there are any): the molecules don't collide anymore and it doesn't behave like a gas. However, it still causes some tiny little drag on ...
5
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1answer
176 views

How to fit, into a cubesat, 29 trackable high drag subsatellites with well-defined aerodynamic profiles

Johnathan McDowell's recent tweet says: The @AerospaceCorp Aerocube-10a cubesat carries 29 small passive high-drag subsatellites used to probe the density of the upper atmosphere. 3 have been ejected ...
3
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2answers
219 views

Number of segment in Wing leading Edges

Can anyone highlight the basis of having 22 NO’s of segment in wing leading edges of space shuttle.
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1answer
131 views

During their climb, when did/do the SpaceShipOne and Two pilots lose all or most of aerodynamic control over the spaceplane?

When, at what altitude and speed, did the pilots of SpaceShipOne and SpaceShipTwo lose all or most of aerodynamic control over their spaceplane when rising into space? The SS1 and SS2 conducted five ...
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2answers
1k views

How do we control a Reentering Capsule in the denser part of the atmosphere?

My question is: How do we control a Reentering Capsule in the denser part of the atmosphere? How does the aerodynamics of the Reentry vehicle workout? In other words, how does a reentry module ...
2
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1answer
50 views

How much heat is reabsorbed by a high-speed object?

I have been playing around with an app to demonstrate high speed objects entering earth's atmosphere. I am using the drag equation to approximate how much kinetic energy gets converted into heat at ...
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1answer
196 views

Using side thrusters on a missile to create an angular acceleration

Assume a rocket is standing on the ground with mass = 1000 kg, and near the top of rocket we apply a force of 100 N for say 1 sec, now assume that this is sufficient to tip the rocket over/start ...
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1answer
179 views

How to calculate the lowest possible altitude a satellite can orbit at due to aerodynamic heating if provided with a sufficient propulsion system?

If a satellite is equipped with a propulsion system which is enough for compensating the local drag and maintaining the orbit, then aerodynamic heating would be the limiting factor for attaining the ...
2
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1answer
96 views

Shape of satellite launch vehicle

I was watching videos on YouTube, and I came across a fact that satellite launch vehicle has shape like a nose or you can ogive shape and I search on Google related to that, and I found that it ...
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69 views

Have studies / worked examples, including mass figures, been published for these reentry methods for reusable upper stages?

(Related: is there a general rule of thumb for thermal protection systems?) For a fully-reusable launch vehicle to be developed, we need a lightweight thermal protection system and method for (...
2
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1answer
218 views

Looking for dataset of trajectory data consisting of latitude, longitude, altitude and time

I am working on a project in which I need to cluster trajectories of different type of flying objects like rocket, plane, missile, etc. For that I am looking for a database or data-set which contains ...
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0answers
137 views

Disadvantage of interstage trusses on Soyuz launch vehicle?

Brian Tompsett gave a detailed explanation of the advantages of the trussing in his answer to the question Why do the Russians use these fence-like interstage fairings? The gap between Stage II and ...
6
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2answers
329 views

What was the actual Q-alpha limit for Saturn/Apollo launches, and what was the typical max Q-alpha?

Organic Marble's answer to a previous question about Apollo abort limits clarified that the figure of concern was the product of dynamic pressure (Q) and angle of attack (alpha), with the 100% level ...
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1answer
52 views

Calorically perfect gas calculations of re-entry vehicles

We know that pressure is least sensitive to high temperature gas effects. Thus, how much of calorically perfect gas calculations (for pressure alone) are used in space vehicle design? Historically, ...
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1answer
399 views

Why was the nose cone on the Space Shuttle's external tank pointy?

Inspired by comments under this answer to this question Just how pointy does a rocket's nosecone need to be? (see also Why are the nose cones of current spacecraft less pointy?) Why was the ...
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2answers
4k views

Golfball Dimples on spaceships (and planes)?

The best of us get stupid ideas which run through our heads day in and day out without finding an answer. That's why I came here: A golf ball has dimples to reduce drag and increase flight distance (...
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1answer
79 views

Is it useful to exploit turbojets or turbofans for rockets like that (for mid & heavy-lift ones)? [duplicate]

In fact, Atmo is very hostile for classical rockets. It makes them too sizable, heavy & inefficient as well. To shift this situation needs to get another propellant, but we have fallen short here. ...
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3answers
547 views

Would a standard gravity turn still be the most optimal path to orbit if Earth did not have an atmosphere?

If Earth had no atmosphere, then would a standard gravity turn still be the most optimal path to orbit? Why or why not?
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4answers
1k views

Just how pointy does a rocket's nosecone need to be?

There are some beautiful images of the Qu8k rocket launch on this web page and I show a few below. There's a video (below) and the PDF Qu8k Final By Derek Deville, November 27, 2011 The stainless ...
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0answers
23 views

Required speed for interplanetary aerodynamic effects [duplicate]

In the atmosphere, craft may use aerodynamic effects to their benefit. As you start getting higher in the atmosphere, the atmosphere becomes rarified, requiring you to model the atmosphere not as a ...
1
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1answer
590 views

Which components do we calculate for center of pressure? Where is the distance of components while computing the cp and cg of a rocket?

everybody! I have 4 questions about center or pressure (cp) and center of gravity (cg) of a rocket system. Questions 1) While computing the center of pressure of rocket system, which components do ...
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2answers
4k views

What are the pros and cons of Aerospike nosecones?

Some rockets, mainly (only?) ICBMs have Aerospike nosecones Why are they preferred in lieu of traditional nose cones? Illustrations: An aerospike nosecone on a trident ICBM Video including the ...
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3answers
307 views

Can more thrust come from launching parallel to water?

Would having the exhaust of a rocket or air breathing engine in an early stage in close proximity to water on a horizontal launch provide more thrust? Could a rocket launch off water horizontally in ...
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0answers
138 views

Why are hexa airfoils used on rockets despite having more drag that diamond airfoils?

I was doing a study on airfoils shape for a rocket. I tested the diamond and the hexagonal airfoil with Missile DatCom, RasAero and the Shock Expansion theory and from my results it seems like the ...
2
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1answer
249 views

How high could a weather balloon be used on Mars without rupturing? [duplicate]

What is the maximum height could a weather balloon achieve on Mars without rupturing? Assume that the balloon is adapted for Mars' atmosphere and gravity from standard high altitude balloons used on ...
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0answers
70 views

Reducing the aerodynamic drag of multi-engined rockets: aft wake area

Have there ever been thoughts of reducing the aerodynamic drag that results from the empty space between rocket engines? More precisely, this extremely low-pressure area sucks up ambient air and ...
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0answers
224 views

Analyzing Amateur Rocket Stability and Range Safety

I am working with a university bunch of other university students on building a very large amateur rocket. Our objective with this rocket is just to go very high, with no significant payload or ...
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0answers
30 views

Air flow over an airfoil [closed]

We know that in real viscous flow, boundary layer exists around the airfoil and there will be a separation point which flow starts to separate from the back of the airfoil( velocity gradient equal ...
15
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1answer
1k views

Soyuz Steering during Re-Entry

In this youtube video, it talks about steering Soyuz by changing lift. Why does roll rotation help in changing lift and also helping in cross range steering? I am looking for an answer from ...
6
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1answer
589 views

The aerodynamic stability of the truncated cone shape

Can someone explicate the stability of the truncated cone shape of the reentry vehicle of a spaceship when moving in the atmosphere with its bottom facing forward? It seems counterintuitive that it ...
2
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1answer
378 views

Is a ballistic blimp entry possible on this way?

Could the entry of Mars with balloons work by inflating to equalize with the atmospheric air pressure, while establishing buoyancy before meeting the ground? Would a balloon pop if dropped from space?...