eccentricity trouble

[Guest Lenny Zaman]

Hello,i'm having trouble keeping the eccentricity small enough to complete a steady orbit...is there any function built in the voyager to keep the Vvel and especially the Vacc very low, close to 0?i've been experimenting with getting into stable orbit...so far i've found out that it requires constant application of small thrust bursts to keep the Vvel and Vacc small enough to maintain altitude thus zero eccentricityThanks in advance(i'm not even thinking of flying the shuttle in space.. i'll take the red 'dart' till i'm comfy in space)Cheers

[PeterR 9]

I just took my first flight in the Glider last night. I found that it's much easier to address the difference between the periapsis and apoapsis distances than fighting the vertical velocity and eccentricity. Until you reach a circular orbit, Vvel continues to change depending upon whether you're approaching the narrow part of your non-circular orbit or the wide part. So, what I did was this:1. Make sure that you have the Orbit mode on one of the MFDs.2. When you reach periapsis, the solid dot on the orbit, apply prograde thrust (in the direction of flight). You'll see that your eccentricity (Ecc) drops and the periapsis distance (PeD) increases toward the apoapsis distance (ApD).3. Turn off the thrusters as soon as your Ecc starts to go back up or you'll negate your efforts.4. Wait until you get to periapsis again and repeat. Eventually, PeD will be near or the same as ApD and Ecc will be at or near zero. Then, your Vvel will also be near or at zero since your orbit is no longer eccentric.I guess you could also apply retrograde thrust at the apoapsis point (the hollow dot on the orbit) to reduce the ApD in addition to prograde thrust at PeD but I didn't try that. I would think that would get you a circular orbit sooner but I'm just a newbie at this space flight stuff.Peter http://bfu.avsim.net/sigpics/PeterR.gifBFU Forums ModeratorRenegade/Seawolf Design Group (RSDG)[table border=2 cellpadding=0 cellspacing=1][tr][td][table border=0 cellpadding=8 cellspacing=0][tr][td bgcolor=#6f0000]http://bfu.avsim.net/sigpics/logo75t.gif[/td][td align="center" bgcolor=#FFFFF6]Bush Flying Unlimited"At home in the wild"Looking for adventure? Come join us! * [link:bfu.avsim.net|Web Site] * [link:www.cafepress.com/bfu,bfu2,bfu3,bfu4|BFU Store] * [link:bfu.avsim.net/join.htm]Join!][/td][/tr][/table][/td][/tr][/table

[Guest Lenny Zaman]

"...but I'm just a newbie at this space flight stuff."that makes two of us :)thanks for the help.Will certainly try it...and of course my current goal is to attain circular orbit around Earth but i'm looking forward to getting to the ISS :)I've already managed to synchronise the planes of my orbit and that of the ISS but by that time i was drifting off around 5000km altitude... Cheers

[PeterR 9]

I haven't yet started on synchronising orbital planes and speeds. I'm currently focusing on the two ends: achieving a good orbit from a ground takeoff and moving the glider between docking ports on the ISS. Once those work fine, I'll be moving on to syncing.Have you tried the DeltaGlider II? It's still a beta version but has so many cool buttons and switches as well as several auto-pilot programs. It's all spread across three panels. Very cool! You can download it here:http://orbiter.dansteph.com/download/DeltagliderII_Setup.phpMake sure you have OrbiterSound 2.5 installed first. And, for best results, run Orbiter at 1152x864 or higher so you don't have to pan left/right to see all the stuff on the panels.Peter http://bfu.avsim.net/sigpics/PeterR.gifBFU Forums ModeratorRenegade/Seawolf Design Group (RSDG)[table border=2 cellpadding=0 cellspacing=1][tr][td][table border=0 cellpadding=8 cellspacing=0][tr][td bgcolor=#6f0000]http://bfu.avsim.net/sigpics/logo75t.gif[/td][td align="center" bgcolor=#FFFFF6]Bush Flying Unlimited"At home in the wild"Looking for adventure? Come join us! * [link:bfu.avsim.net|Web Site] * [link:www.cafepress.com/bfu,bfu2,bfu3,bfu4|BFU Store] * [link:bfu.avsim.net/join.htm]Join!][/td][/tr][/table][/td][/tr][/table

[Guest Lenny Zaman]

thank you very muchtoday i completed a round tripi took off of Kennedy, went into 210km orbit(got the Ecc to 0.00000 ;-)) then aligned the plane with that of the ISS, made a prograde burn to get intersection with ISS path, succesfully found the ISS, made a 100% perfect docking, transferred fuel and O2+N2then undocked, but the ISS was not in a good orbit to land at Cape Canaveral, so i adjust my orbit with an Antinormal burn for about 15 minutes, should have kept doing that untill actually leaving orbit as i'll explain laterso i continued till the Dist was 16.55M, made the retrograde burn to reduce periapsis altitude for re-entryall went well, at 130 km ALT, turned prograde again an initiated autopilot reentry mode.ended up about 700km south of cape canaveral, fortunately i still had sufficient fuel so i 'flew' the bird back to Cape, though i could've gone for Havana aswellWonderfull experience :DCheers

[PeterR 9]

Good going! I tried a re-entry starting from the ISS but overdid the re-entry burn and landed very short. More practice! ;-)Peter http://bfu.avsim.net/sigpics/PeterR.gifBFU Forums ModeratorRenegade/Seawolf Design Group (RSDG)

[Guest Lenny Zaman]

that's the good thing when flying the Glider...after having refueled at the ISS, i had plenty of fuel to jet me to the cape... ;)but i'm working on it now40