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Whadya mean I'm on fire! I shouldn't burn up yet!

Posted 03-02-2010 at 03:15 AM by Bendarr

The fumbling misadventures of someone who really shouldn't be behind a joystick.

I had orbiter a while back but ended up losing in in a systems crash a while ago and decided to give it another go. Went ahead, got the files, the sound files, the DGIV (wonderful craft!) then tried to read some manuals. Later on with my head spinning I decided "What the hey, nothing like hands on and I've launched the DGIV into orbit using the autopilot several times and took some notes. And I've got it configured for invulnerability while I learn. What could go wrong with a manual attempt?"

(cue ominous music)

There I am at KSC. Sitting on the runway, just a few button pushings away from an autopilot ascent and I decide to go manual. I slam the throttle full bore and go screaming towards the end of the runway. I hear the computer saying "80 knots." I find myself thinking "I have no idea how fast a knot is but I guess I'm doing all right." then I hear "Rotate." and I find myself thinking "Well the wheels are rotating all right. Did I have the brakes on earlier or something? ...... Uh oh, the end of that runway is getting closer and closer. Better pull back on that stick." In amazement and glee I can tell the nose goes up and I'm airborne!! ok, the heading of the ISS is roughly 42 now lets look at my notes ...... WHERE ARE MY NOTES!! Me with all the memory span of a Ferrett at the stick of this craft? Ah well, what could happen? I slowly proceed to turn until the heading is roughly 42degrees. I'll fix that later. ok, time for some altitude! I pull the nose as high as she'll go and claw for altitude. BONG! the computer makes a noise and I look and realize that I still had the landing gear down and the stresses were getting ready to tear them off. I hit the button to raise them and before they could retract ....... riiiiippp!!
"Warning! Warning! Warning!" I keep hearing time and time again. I did what any pilot would do........ I turned off my speakers and pretended it never happened.

I climbed for orbit, clawing for altitude, totally forgetting about horizontal speed I raced for destiny. I ended up with the nose pitching down no matter what I did. What was wrong? Why wasn't I getting enough speed? I had the engines on full! I made it to the upper reaches of the atmosphere and found myself dropping and then rising again. It was a yo-yo ride. I switched to a external view to try to get a clue and this is what I saw.........





After such a fiery ascent to a glorious death I decided to reset and take a break. Later on after watching the autopilot one more time I realized my mistake. During the ascent I forgot to turn the "Turbo pumps" on!

More to come at a later time!
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Comments

  1. Old Comment
    yo-yo ride...cue my one of my spaceflight words! phugoid! Great blog entry, very amusing
    Posted 03-03-2010 at 08:42 PM by kneecaps kneecaps is offline
  2. Old Comment
    Bendarr's Avatar
    Glad you like it. There will be more in the future but a couple of days ago I came home and found 2 circuit breakers tripped in the house, the kids gone, and my power supply, C drive and D drive toast on my computer. So I'm rebuilding. If it's any thought one of the first things I did (after replacing hardware and some software) was to rebook mark this site so you can expect to see more of me.
    Posted 03-05-2010 at 01:11 AM by Bendarr Bendarr is offline
  3. Old Comment
    unknown_orbiter's Avatar
    Hahaha this is great! The landing gear retraction is actually something I never forget because as a real-world pilot I do mental pre-mid-post checklists, and landing gear is a major aspect of those checks. You mention the TurboPump being a major factor in your ascent fail here. I actually quite often (more than 80% of the time) forget/decide not to use the TurboPump during my ascents. The DGIV has a powerful enough engine to get up on its own, but the TurboPump increases that for better fuel efficiency as well as a speedier ascent. The real reason that you were burning up on ascent was because of your landing gear. Those holes in the bottom of your ship cause a LOT of drag, as well as friction and therefor heat buildup. That is why you were on fire, and why you couldn't ascend well at all after the fact. I assume you already have taken extensive notes on the ascent autopilot, but here's a nice rundown of the basic steps:
    Take off, maintain 30 degrees Angle of Attack (AoA) until your landing gear is up.
    Maintain 30 degrees as you turn to either the azimuth of your target (42 degrees in the case of the ISS), or to 90 degrees to reach a simple Earth orbit (uses the rotation of the earth to assist in the launch).
    Once you are on the correct heading, pitch up to 70 degrees. At this point, turn on the TurboPump if you wish.
    Maintain this setup until ~150 km above the Earth's surface, and then begin to slowly yet steadily decrease your AoA to maintain decent vertical speed while increasing your horizontal velocity.
    At the end of your ascent, you should have to be FORCING the nose of the ship to stay at 0 degrees AoA to really extend that orbit out.
    The easiest way I found when I was learning to get into a circular orbit (before I started doing calculations and interpreting the Orbit MFD values), was to just look at the Orbit MFD graphic.
    Press the PRJ button until in the top right of the Orbit MFD it says SHP. As you ascend, watch the green line representing your ship. You should also see a small hollow green circle near the end of the green line. This is your apoapsis, the highest point of your orbit.
    If your line is behind the circle, lower AoA more. If it in front of the circle, pitch up more. At a point you will reach a nice equilibrium, and you will stay at that AoA until you begin to level off to complete your orbit at the correct altitude. The key here is to PRACTICE PRACTICE PRACTICE!
    I am going to be adding a tutorial video on ascending into Orbit soon, so watch out for it in the tutorials section.
    Good luck!
    Posted 03-10-2010 at 05:15 AM by unknown_orbiter unknown_orbiter is offline
 

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