STS deorbit and landing

[groberto]

People, this is my very 1st post. I hope you will like it.

I have spent some time trying to land the shuttle as close to real world as i was able to.

I started from these STS-5 reentry real data:



I have digitalized them and compared them with data recorded during my flights:
The thick lines are my data, the thin lines are the STS-5 data




Even more important is the Altitude vs Velocity plot.
I am pretty proud of this.




Comments please!

Thank you Martin! :thumbup:
I also thank you all, the people that contributed to Orbiter, and all the people that write on this forum. You all are really great!!
Greetings :tiphat:
Roberto

 

[Stevodoran]

wow tried to make ir as real as possible and you did:thumbup:

 

[Thundersnook]

For some reason I couldn't open the pictures But as far as I see this is pretty accurate and impressive work!

 

[orb]

For some reason I couldn't open the pictures But as far as I see this is pretty accurate and impressive work!

Check them again. They should be fine now.

 

[Thundersnook]

Check them again. They should be fine now.

Thank you! Yup, It works! :thumbup:

 

[mjessick]

You can do a lot with altitude(h) as a function of velocity (v) charts.

You can draw curves of constant specific energy (Es) in altitude units:
Es = h + v*v / (2 g) where g = gravity acceleration, h=alt, v=speed
This gives an energy value expressed in length units. For a particular value of Es, if you did a quick constant energy zoom climb trading all your kinetic energy for potential energy, how high (ideally) would you get when your velocity reached zero? An altitude equal to Es. (This is the idea behind expressing energy as a height (length units))

You can draw dynamic pressure limit boundary contour lines in h-v space, as long as you know density as a function of height as we know perfectly in Orbiter.

density * v*v*v lines can be used to suggest heating rate limit boundaries in Orbiter for some vehicles.

Scramjet operating limits can be drawn.

The rate of change of Es is specific excess power (the time rate of change of specific energy).
Ps = d(Es)/dt = d(h)/dt + (v/g)*(acceleration)
where d(Es)/dt is the time derivative of Es,
dh/dt is the climb rate (derivative of height with time)
and acceleration is the derivative of velocity with respect to time

Ps curves are complicated to draw for a vehicle like the DG-S (for example), because you are actually drawing:
Ps = velocity * (Thrust - Drag)/weight, (this is correct for dh/dt = 0 or level flight)
so you need to know all about the aerodynamics, and the thrust of the rocket and the scramjets, and the atmosphere model.

This concept can be used to maximize energy gain per time in climbs. For example, you could plot contours of constant specific energy, and also your vehicle's contours of specific excess power. Then, to gain energy fastest, you follow the highest values of Ps across the h-v chart: Basically, this is where the Ps contour is just tangent to an Es contour. This is the path through the h-v space with the fastest energy gain.

Those are hints toward pretty much all of the basic flight performance secrets needed for fast climb and also some for fast reentry for rocket racing