We've had many challenges before, but I wanted to post a new one (In part because I'm looking for some data 
)
Challenge: Get to LEO with minimal delta-v. Place your spacecraft in a 35km x 35km orbit (+-5km, difference <7km).
Once completed, provide the following information:
IF SSTO:
Initial TWR:
Delta-v used:
Fuel % remaining:
Engines used:
Launch #:
Did you exit to turn on aerodrag (Y/N):
Apoapsis:
Periapsis:
Description of gravity turn method (optional):
IF Multi-staged:
For each stage---
Initial TWR:
Delta-v used:
Engines used:
End of individual stages---
Launch #:
Did you exit to turn on aerodrag (Y/N):
Apoapsis:
Periapsis:
Description of gravity turn method (optional):
What I'm looking for in particular is to see the range of delta-v used to get into LEO and see how TWR affects that.
RULES:
No cheats.
All stages must use all engines at once (I've got to analyze this data, ok?).
Accurate reporting of all data to the best of your ability and knowledge.
Optional: If you could launch the same craft a few times, recording the data, that gives information about the range. Also, launching the same craft using the aero drag or no aero drag. If you really want to help out, use different engines and twr combinations following the same gravity turn method. One top-notch thing you could do is take existing spacecraft you like and test those, reporting the results.
Criteria: (I'm trying to make it fair for everyone. It's not all about the smallest, lightest, because there are so many different classes. Not all craft compete)
(SSTO) Different classes of initial twr (1.0 to 2.0 in 0.1 increments)
(Multi-staged) Initial twr of both stages (Using increments of 1/4 for stages after first) (Ex. TWR 1st stage 1.4, 2nd stage 1.0 is similar enough to 1.4 then 1.1)
Drag/no drag.
Delta-v used.
Engine type.
Number of times orbit was reached for the purpose of this challenge.
BONUS: Calculations. If someone could calculate the minimal delta-v to orbit, that would be great.
I will consider posting winners using a combination of these listed criteria, though it may become too much. I also retain the right to reject all data that doesn't fit my preconceived notion.
Goal: The goal is to collect data on reaching LEO so that twr and other variables can be optimized for takeoff.
Thank you all, and I hope you all enjoy it!
P.S. Calculating deltaV: isp*9.8*ln(M0/[M0-Mfuel*.9*%left/100%]) where M0=mass at takeoff, Mfuel is the wet mass (all mass for all fuel tanks), and %left is the %fuel left after orbit.
)Challenge: Get to LEO with minimal delta-v. Place your spacecraft in a 35km x 35km orbit (+-5km, difference <7km).
Once completed, provide the following information:
IF SSTO:
Initial TWR:
Delta-v used:
Fuel % remaining:
Engines used:
Launch #:
Did you exit to turn on aerodrag (Y/N):
Apoapsis:
Periapsis:
Description of gravity turn method (optional):
IF Multi-staged:
For each stage---
Initial TWR:
Delta-v used:
Engines used:
End of individual stages---
Launch #:
Did you exit to turn on aerodrag (Y/N):
Apoapsis:
Periapsis:
Description of gravity turn method (optional):
What I'm looking for in particular is to see the range of delta-v used to get into LEO and see how TWR affects that.
RULES:
No cheats.
All stages must use all engines at once (I've got to analyze this data, ok?).
Accurate reporting of all data to the best of your ability and knowledge.
Optional: If you could launch the same craft a few times, recording the data, that gives information about the range. Also, launching the same craft using the aero drag or no aero drag. If you really want to help out, use different engines and twr combinations following the same gravity turn method. One top-notch thing you could do is take existing spacecraft you like and test those, reporting the results.
Criteria: (I'm trying to make it fair for everyone. It's not all about the smallest, lightest, because there are so many different classes. Not all craft compete)
(SSTO) Different classes of initial twr (1.0 to 2.0 in 0.1 increments)
(Multi-staged) Initial twr of both stages (Using increments of 1/4 for stages after first) (Ex. TWR 1st stage 1.4, 2nd stage 1.0 is similar enough to 1.4 then 1.1)
Drag/no drag.
Delta-v used.
Engine type.
Number of times orbit was reached for the purpose of this challenge.
BONUS: Calculations. If someone could calculate the minimal delta-v to orbit, that would be great.
I will consider posting winners using a combination of these listed criteria, though it may become too much. I also retain the right to reject all data that doesn't fit my preconceived notion.
Goal: The goal is to collect data on reaching LEO so that twr and other variables can be optimized for takeoff.
Thank you all, and I hope you all enjoy it!
P.S. Calculating deltaV: isp*9.8*ln(M0/[M0-Mfuel*.9*%left/100%]) where M0=mass at takeoff, Mfuel is the wet mass (all mass for all fuel tanks), and %left is the %fuel left after orbit.
