Quote from: edkyle99 on 05/16/2017 02:32 pmQuote from: BabaORileyUSA on 05/16/2017 01:27 pmThis was NOT a flight to GTO! This used a super-synchronous transfer orbit.Don't the parameters at insertion (315 km altitude, 10,025 m/s velocity) indicate a subsynchronous transfer orbit?Quote from: rsdavis9 on 05/16/2017 02:37 pmI calculated it naively with the elliptical orbit and got almost exactly a apogee of geo sync. i.e. 35786 km above earth surface.v=(u*(2/r-1/a))^.5u=GMr=perigee from center of eartha=semimajor axisVelocity seems relative to launch site, since it's 0 at launch and not 408 m/s. Adding this in, you get an inertial frame speed of 10435, for a apogee of about 62000 km, or super-synchronous.
Quote from: BabaORileyUSA on 05/16/2017 01:27 pmThis was NOT a flight to GTO! This used a super-synchronous transfer orbit.Don't the parameters at insertion (315 km altitude, 10,025 m/s velocity) indicate a subsynchronous transfer orbit?
This was NOT a flight to GTO! This used a super-synchronous transfer orbit.
I calculated it naively with the elliptical orbit and got almost exactly a apogee of geo sync. i.e. 35786 km above earth surface.v=(u*(2/r-1/a))^.5u=GMr=perigee from center of eartha=semimajor axis
Quote from: Silmfeanor on 05/16/2017 04:26 pmFrom the update thread - Quote from: Targeteer on 05/16/2017 04:20 pm42698 INMARSAT 5-F4 2017-025A 1401.67min 24.50deg 69839km 381km 42699 FALCON 9 R/B 2017-025B 1410.43min 24.47deg 70181km 384kmDefinitly Super-synchronous.Certainly. Only thing is that upper stage will stay up there for a long time.
From the update thread - Quote from: Targeteer on 05/16/2017 04:20 pm42698 INMARSAT 5-F4 2017-025A 1401.67min 24.50deg 69839km 381km 42699 FALCON 9 R/B 2017-025B 1410.43min 24.47deg 70181km 384kmDefinitly Super-synchronous.
42698 INMARSAT 5-F4 2017-025A 1401.67min 24.50deg 69839km 381km 42699 FALCON 9 R/B 2017-025B 1410.43min 24.47deg 70181km 384km
Pretty good performance. 70k apogee + an inclination reduction.
Quote from: hans_ober on 05/16/2017 04:41 pmPretty good performance. 70k apogee + an inclination reduction.Excellent performance. GTO-1570.
Yes, but it still processes the inc+circ delta V needed for GSO circular. That is the point I think (how much work has the payload to do until it gets to operational orbit).
I'm getting this from the calc. Am I putting something wrong in?http://www.satsig.net/orbit-research/delta-v-geo-injection-calculator.htm
Quote from: hans_ober on 05/16/2017 04:41 pmPretty good performance. 70k apogee + an inclination reduction.This one looks to have been a hotter performer than previous Falcon 9s. I'm becoming more convinced that this is an upgraded variant. - Ed Kyle
Quote from: edkyle99 on 05/16/2017 04:46 pmQuote from: hans_ober on 05/16/2017 04:41 pmPretty good performance. 70k apogee + an inclination reduction.This one looks to have been a hotter performer than previous Falcon 9s. I'm becoming more convinced that this is an upgraded variant. - Ed KylePossibly, but we've also probably never seen max performance from a previous Falcon 9.
So assuming that this is max performance for the F9, at least for the moment, and as noted above by others, a 6,070 KG payload to GTO-1570, does this give us a clue what the max payload would for a GTO launch? I seem to recall seeing GTO-1800 is acceptable for customers. I don't have the knowledge to either know that GTO-1800 is ok, or the math to work backwards to get the payload. I would be interested on any thoughts by those more knowledgeable than I. I also wonder what portion of commercial payloads would exceed the mass we now think F9 is capable of. It seems like a smaller portion is restricted to the competition.
Quote from: Dante80 on 05/16/2017 04:52 pmI'm getting this from the calc. Am I putting something wrong in?http://www.satsig.net/orbit-research/delta-v-geo-injection-calculator.htmI don't know what algorithm that site is using, but I'm using this: https://www.reddit.com/r/spacex/wiki/launches/gto_performance and here is the code: https://gist.github.com/anonymous/aa3397ea848d2e2d6986804f027e286eThis is a Lou Scheffer approved method. (See https://forum.nasaspaceflight.com/index.php?topic=36954.0 from which is based). I dont trust that site, and it seems neither does he.
Quote from: Billium on 05/16/2017 05:58 pmSo assuming that this is max performance for the F9, at least for the moment, and as noted above by others, a 6,070 KG payload to GTO-1570, does this give us a clue what the max payload would for a GTO launch? I seem to recall seeing GTO-1800 is acceptable for customers. I don't have the knowledge to either know that GTO-1800 is ok, or the math to work backwards to get the payload. I would be interested on any thoughts by those more knowledgeable than I. I also wonder what portion of commercial payloads would exceed the mass we now think F9 is capable of. It seems like a smaller portion is restricted to the competition.The same performance would put 6820 kg to GEO-1800, assuming the stage dry mass if 4500 kg and MVac I_sp is 348 seconds.
Quote from: envy887 on 05/16/2017 06:16 pmQuote from: Billium on 05/16/2017 05:58 pmSo assuming that this is max performance for the F9, at least for the moment, and as noted above by others, a 6,070 KG payload to GTO-1570, does this give us a clue what the max payload would for a GTO launch? I seem to recall seeing GTO-1800 is acceptable for customers. I don't have the knowledge to either know that GTO-1800 is ok, or the math to work backwards to get the payload. I would be interested on any thoughts by those more knowledgeable than I. I also wonder what portion of commercial payloads would exceed the mass we now think F9 is capable of. It seems like a smaller portion is restricted to the competition.The same performance would put 6820 kg to GEO-1800, assuming the stage dry mass if 4500 kg and MVac I_sp is 348 seconds.So we are still no where near the 8300kg promise land... Figures... Ref http://www.spacex.com/falcon9
Quote from: LouScheffer on 05/16/2017 02:41 pmQuote from: edkyle99 on 05/16/2017 02:32 pmQuote from: BabaORileyUSA on 05/16/2017 01:27 pmThis was NOT a flight to GTO! This used a super-synchronous transfer orbit.Don't the parameters at insertion (315 km altitude, 10,025 m/s velocity) indicate a subsynchronous transfer orbit?Quote from: rsdavis9 on 05/16/2017 02:37 pmI calculated it naively with the elliptical orbit and got almost exactly a apogee of geo sync. i.e. 35786 km above earth surface.v=(u*(2/r-1/a))^.5u=GMr=perigee from center of eartha=semimajor axisVelocity seems relative to launch site, since it's 0 at launch and not 408 m/s. Adding this in, you get an inertial frame speed of 10435, for a apogee of about 62000 km, or super-synchronous.Using the posted picture in the update thread after SECO-2 we have 4 data points of R (above ground) and V:315km - 10025m/s,321km - 36060km/h=10017m/s420km - 35770km/h=9936m/s486km - 35561km/h=9878m/susing the formular above with GM=3.98438E14 and an Earth radius of 6371km I get an average semimajor axis of about 21340+-50km or Apogee of ~ 29552km.Adding the 408m/s to V I get an average semimajor axis of 38407+-125km or Apogee of ~ 63688km. Do smaller errors of the first set hint that it is wrong to add 408m/s? Yet the apogee would be well below GEO strongly suggesting that the later is the better aproximation.The question for me remains with this analysis what V really is, velocity along the flight path or relative to ground below the stage or relative to launch site? Edit the TLEs posted show that adding 408m/s seems to be the right way to do it.