-
Horizontal vs. vertical integration
by
peter-b
on 23 Oct, 2011 18:28
-
Sorry if this has been asked before, but...
What are the relative (dis)advantages of horizontal and vertical payload integration?
Why does Soyuz in Guiana have its payloads integrated vertical, while Soyuz at Baikonur have its payloads integrated horizontally?
Why is (IIRC) the DoD requiring vertical integration for all of its payloads?
Thanks for any info you can provide. :-)
-
#1
by
Jim
on 23 Oct, 2011 18:33
-
Payloads aren't cantilevered while fueled with vertical. Vertical provides 360 access at the pad
-
#2
by
edkyle99
on 23 Oct, 2011 19:25
-
Sorry if this has been asked before, but...
What are the relative (dis)advantages of horizontal and vertical payload integration?
Why does Soyuz in Guiana have its payloads integrated vertical, while Soyuz at Baikonur have its payloads integrated horizontally?
Why is (IIRC) the DoD requiring vertical integration for all of its payloads?
Thanks for any info you can provide. :-)
I suspect that one advantage of vertical payload integration is that launch vehicle processing can be more isolated from the payload, and therefore simplified. With horizontal integration, the rocket has to be integrated without payload, then rolled to the pad for propellant testing, then rolled back to the hanger for payload integration, then rolled *back* to the pad to be reconnected yet again to the propellant and electrical umbilicals, etc.. With vertical integration, the rocket never leaves the pad, or launch platform, between dress rehearsal, payload stacking, and launch.
- Ed Kyle
-
#3
by
peter-b
on 23 Oct, 2011 19:39
-
Vertical provides 360 access at the pad
SpaceX obtain 360 degree access to their launcher in the horizontal integration facility by simply providing a motorised rotator mechanism on the stand...
Are there any advantages to horizontal integration? I guess that the buildings are cheaper and you don't have all the safety faff that comes with working at height...
-
#4
by
joek
on 23 Oct, 2011 20:01
-
... With horizontal integration, the rocket has to be integrated without payload, then rolled to the pad for propellant testing, then rolled back to the hanger for payload integration, then rolled *back* to the pad to be reconnected yet again to the propellant and electrical umbilicals, etc...
Is that typical in practice? Looking at, e.g., Sooyuz, the first time the LV sees the pad appears to be after everything is integrated: (1a) integrate payload + upper stage; (1b) integrate 1st + 2nd + 3rd stage; (2) integrate 1a + 1b; (3) rollout complete stack to pad.
edit: correction, 3rd stage vs. upper stage.
-
#5
by
Jim
on 23 Oct, 2011 20:20
-
Vertical provides 360 access at the pad
SpaceX obtain 360 degree access to their launcher in the horizontal integration facility by simply providing a motorised rotator mechanism on the stand...
I was talking spacecraft access.
But anyways, can't rotate the vehicle when attached to the launcher
-
#6
by
peter-b
on 23 Oct, 2011 20:25
-
I was talking spacecraft access.
So was I...
But anyways, can't rotate the vehicle when attached to the launcher
Why not? Do you mean that you can't rotate the vehicle when attached to the strongback? Because I guess that's true.
-
#7
by
joek
on 23 Oct, 2011 20:45
-
Are there any advantages to horizontal integration? I guess that the buildings are cheaper and you don't have all the safety faff that comes with working at height...
Also potentially less time spent occupying the pad, but that (and benefit) depends on other factors (e.g., launch rate, integration caobility/throughput, etc.). As you suggiest, at present I'd guess the primary benefit is cheaper facilities.
The
rationale given by Arianespace:
The vertical integration of Soyuz payloads is the primary difference in the Spaceport's launch vehicle processing as compared to the long-operating Soyuz facilities at Baikonur Cosmodrome in Kazakhstan and Plesetsk Cosmodrome in Russia. This vertical procedure enables payloads to be installed as traditionally performed with Western launch systems – and is a change from the horizontal integration utilized at the Baikonur and Plesetsk Cosmodromes.
So presumably there are enough payloads which require vertical integration to justify the additional facilities cost. Or maybe since existing Arianespace processes/payloads are based on vertical ("as traditionally performed"), it was more effective to continue/extend that with Soyuz.
-
#8
by
hop
on 23 Oct, 2011 20:53
-
Are there any advantages to horizontal integration? I guess that the buildings are cheaper and you don't have all the safety faff that comes with working at height...
If your LV is integrated horizontally, then substantial infrastructure is required for vertical payload integration, as we see with Soyuz at CSG.
If your LV already has significant elements that are integrated vertically, then the additional infrastructure required for vertical payload integration is much less significant. Large solids pretty much rule out horizontal LV integration.
-
#9
by
joek
on 23 Oct, 2011 22:45
-
If your LV is integrated horizontally, then substantial infrastructure is required for vertical payload integration, as we see with Soyuz at CSG.
If your LV already has significant elements that are integrated vertically, then the additional infrastructure required for vertical payload integration is much less significant. Large solids pretty much rule out horizontal LV integration.
Was trying to think of a way to express that, or at least categorize the variations, and what came to mind is the following matrix. No claim as to its utility; corrections appreciated. Thanks.
Columns represent LV assembly/integration method. Rows represent payload-to-LV integration method. Intersection represents whether a given combination is used. V = vertical; H = horizontal.
| PL+LV \ LV | H (off-pad) | V off-pad | V on-pad |
| H (off-pad) | Y(1) | N | N |
| V off-pad | ? | Y(3) | N |
| V on-pad | Y(2) | ? | N(4) |
Notes:
1 - Most (all?) Russian, Falcon 9, Taurus II, …
2 - D-IV, Souyz CSG
3 - Atlas V, VAB (Saturn, Shuttle)
4 - At one time, none today?
-
#10
by
Jim
on 23 Oct, 2011 23:34
-
I was talking spacecraft access.
So was I...
But anyways, can't rotate the vehicle when attached to the launcher
Why not? Do you mean that you can't rotate the vehicle when attached to the strongback? Because I guess that's true.
Not just the strongback but the holddown system. And that is the time spacecraft want to do final closeouts. This is also while they are powered up and that has to be through the umbilical.
-
#11
by
edkyle99
on 24 Oct, 2011 00:58
-
... With horizontal integration, the rocket has to be integrated without payload, then rolled to the pad for propellant testing, then rolled back to the hanger for payload integration, then rolled *back* to the pad to be reconnected yet again to the propellant and electrical umbilicals, etc...
Is that typical in practice? Looking at, e.g., Sooyuz, the first time the LV sees the pad appears to be after everything is integrated: (1a) integrate payload + upper stage; (1b) integrate 1st + 2nd + 3rd stage; (2) integrate 1a + 1b; (3) rollout complete stack to pad.
edit: correction, 3rd stage vs. upper stage.
Wet dress rehearsals are, or have been, typical in western practice (i.e. at Kourou, Cape Canaveral, and Tanegashima). Soyuz went through such a test at Kourou prior to spacecraft mating.
At Baikonur, the Soyuz launchers undergo an integrated test on the pad two days prior to launch. I'm not sure if that includes propellant loading. I doubt very much that the hardware doesn't see its first cryo loading until launch day.
- Ed Kyle
-
#12
by
joek
on 24 Oct, 2011 02:20
-
At Baikonur, the Soyuz launchers undergo an integrated test on the pad two days prior to launch. I'm not sure if that includes propellant loading. I doubt very much that the hardware doesn't see its first cryo loading until launch day.
The Soyuz launch campaign flowchart shows 3 days total pad time (after LV assembly and payload integration for entire stack) before launch, and with no other pad time. There could be a separate LV tankinkg/checkout on the pad, altho there's no indication of such in their flowcharts.
If you have a reasonable level of confidence in the LV (which presumably they do?), would there be a good reason for assembling the LV ih the HIF, hauling it out to the pad, tanking/de-tanking/checkout, haluing it back to the HIF, integrating with payload, then hauling it all back out to the pad?
Anyone with first-hand experience care to comment? Thanks.
-
#13
by
butters
on 24 Oct, 2011 03:43
-
Suppose you have an all-liquid launch vehicle suitable for horizontal integration and intended to carry both unmanned and manned payloads. Being as the launch complex would need to provide a means for passengers to board the payload atop of the vertical stack on the launch pad, does it make any sense to integrate the payload horizontally, or does it make much more sense to incorporate vertical payload integration capability into the same pad facility used for passenger ingress? Further suppose that your company is well-known for maximizing commonality...
You see what I'm getting at. I wouldn't be surprised if SpaceX moves to vertical payload integration at some point. The combination of horizontal off-pad LV integration and vertical on-pad payload integration seems to be ideal from an operational standpoint, and the higher capital investment is a lot easier to justify if you want to support manned launches from the same pad.
-
#14
by
manboy
on 24 Oct, 2011 04:02
-
Suppose you have an all-liquid launch vehicle suitable for horizontal integration and intended to carry both unmanned and manned payloads. Being as the launch complex would need to provide a means for passengers to board the payload atop of the vertical stack on the launch pad, does it make any sense to integrate the payload horizontally, or does it make much more sense to incorporate vertical payload integration capability into the same pad facility used for passenger ingress? Further suppose that your company is well-known for maximizing commonality...
You see what I'm getting at. I wouldn't be surprised if SpaceX moves to vertical payload integration at some point. The combination of horizontal off-pad LV integration and vertical on-pad payload integration seems to be ideal from an operational standpoint, and the higher capital investment is a lot easier to justify if you want to support manned launches from the same pad.
Given the added costs of vertical integration it really doesn't seem worth it just to have commonality with a crew launch tower. Plus SpaceX keeps going on about how they want to decrease the time from hanger to pad so I don't see them moving towards the route you suggested.
-
#15
by
woods170
on 24 Oct, 2011 05:35
-
Wet dress rehearsals are, or have been, typical in western practice (i.e. at Kourou, Cape Canaveral, and Tanegashima). Soyuz went through such a test at Kourou prior to spacecraft mating.
Actually.. no it didn't. VS01 did not perform a wet dress rehearsel. The very first time fuels and oxidizers were loaded into any Soyuz launcher (minus the Fregat upper stage) at CSG was 20 october, the day of the botched first launch attempt of VS01
Earlier this year, in april, a different Soyuz launcher was rolled out to the launchpad for functional and fit checks. They did not load fuels and oxidizer into that one. Arianespace did perform a virtual countdown and lift-off. But, without tanking, that's considered to be a dry dress rehearsal. See
this Arianespace update and
this one for more information
At Baikonur, the Soyuz launchers undergo an integrated test on the pad two days prior to launch. I'm not sure if that includes propellant loading. I doubt very much that the hardware doesn't see its first cryo loading until launch day.
- Ed Kyle
As I mentioned above: the first three stages of the Soyuz launcher generally do not see their first loads of fuel and oxidizers until the day of the first launch attempt.
-
#16
by
Phillip Clark
on 24 Oct, 2011 06:45
-
One advantage of integrating the launch vehicle and rolling it out to the pad horizontally is that it minimises the time on the pad, allowing for a rapid re-use of launch pads.
This is how the high launch rate of >80 launches a year was maintained in the Soviet era.
-
#17
by
douglas100
on 24 Oct, 2011 08:57
-
A notable example of that being the launch of Vostok 3 and Vostok 4 a day apart in 1962.
-
#18
by
mmeijeri
on 24 Oct, 2011 09:20
-
One advantage of integrating the launch vehicle and rolling it out to the pad horizontally is that it minimises the time on the pad, allowing for a rapid re-use of launch pads.
Why does this minimise time on the pad?
-
#19
by
mmeijeri
on 24 Oct, 2011 09:23
-
Are spacecraft typically designed to be able to be integrated both horizontally and vertically, or just one of the two?