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It has recently been announced that the A'Mhoine peninsula in Sutherland, Scotland will be host to the United Kingdom's first vertical launch site (assuming they can get anything done with just £30m in grants). Lockheed Martin, Rocket Lab and Orbex have been put forward as launch providers.

It is suggested that the launch site will allow for polar and sun-synchronous orbits, primarily for small satellites:

Launch vehicles taking off from Scotland’s coast in Sutherland will fly to the north, taking routes over the Norwegian Sea between Iceland and Svalbard to ensure debris does not fall on populated areas.

Is there an official word on the range of orbital inclinations to be targeted from A'Mhoine?

And what is the range of launch azimuths available? How much will these be affected by the (sparsely) populated Orkney and Shetland islands?

My observations

A'Mhoine is at a latitude of ~58.5° so this is our minimum possible inclination without plane changes.

For prograde launches, by my rough eyeballing, a very significant dogleg could reach a ~50° inclination, but any less than that would cross over western Norway.

Northerly launches to polar orbits have a fairly wide range, but will be limited by the large number of inhabited islands.

Retrograde inclinations greater than ~98° for typical sun-synchronous orbits are of limited use, but a wide range of Westerly launches over the North Atlantic would be possible (up to a launch azimuth of ~170°).

Another consideration, as pointed out on NASASpaceFlight, is the very large number of oil rigs in the North Sea and North Atlantic. This map shows the areas of activity.

Further Reading

Scott Manley posted a video discussing the A'Mhoine launch site with targets of sun-synchronous and polar orbits. It featured the linked graphic with viable launch azimuths that avoid the Northern Isles. It appears to be hand-drawn though (no, really!) and doesn't reference any official information.

Edit

Gov.uk has a large collection of documents from the many consultations on the prospect of a UK spaceport. As expected however, most of the analysis is concerned with the politics and finance and there appears to be very little detail on the physical feasibility of a launch site.

The closest they seem to come to describing planned launch azimuths is:

...it is important to be clear that, due to its northerly latitude, the UK is only suitable for launching satellites into polar orbit (as opposed to equatorial orbit).

The UK Space Agency's prospectus also briefly mentions sun-synchronous orbits (which are close to Polar orbits anyway):

Launching rockets north from the UK allows access to in-demand polar and sunsynchronous orbits.

Related question about launches from Europe as a whole. This question has more detail on the proposed launch providers.

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    $\begingroup$ You don't want to launch to the east at that high(ish) latitude. You want to launch somewhere between to the north to the northwest (to the south / southwest is pretty much ruled out). A flight path that just skirts just to the west of the Faroe Islands would probably be ideal. $\endgroup$ – David Hammen Jul 17 '18 at 21:47
  • $\begingroup$ Why would launching in a retrograde inclination be of limited use? Such high latitude launch sites are great for achieving very high inclinations since the upper stage doesn't need to burn as much fuel for the inclination change compared to an equatorial launch for example. $\endgroup$ – ChrisR Jul 21 '18 at 17:30
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    $\begingroup$ @ChrisR I mean limited in the sense that the majority of launches are not retrograde. I understand that general use cases of higher-latitude launch sites, but I'm looking for and official description of what inclinations will be targeted. $\endgroup$ – Jack Jul 21 '18 at 17:33
  • $\begingroup$ @ChrisR Launching from high latitudes doesn’t give an advantage over equatorial sites when launching to high/polar inclination if there is a clear northerly or southerly flight azimuth available. $\endgroup$ – Russell Borogove Jul 27 '18 at 19:58
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    $\begingroup$ @ChrisR The launching latitude is strictly the inclination of the orbit you'll get if you launch directly eastward. Ground launch sites typically are not moving at orbital velocity, so the "inclination change" is nearly free if you simply launch to the north. $\endgroup$ – Russell Borogove Jul 27 '18 at 21:48
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The proposed location is actually further west than the map above - on the A'Mhoine peninsular in the Sutherland area of Scotland. Therefore the range of easterly launch angles is slightly increased. A'Mhoine proposed spaceport

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I don't have an official answer for you, but based on Sutherland's location, launches even moderately to the East would fly over populated areas, so they're unlikely. Launches to the West won't happen, since that would counter the benefits you get of launching in the same direction as the rotation of the Earth.

That leaves North: slight retrograde for sun-sync, or strict polar and perhaps slightly away from polar. If I had to guess, I'd say something like 85 to 98 deg inclination direct.

However, having said that, plane changes are certainly possible, of course, so although it might not be the most economical, the final inclination could be almost anything.

Sutherland

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  • $\begingroup$ If possible, a map, even a screenshot would be really helpful here. Readers are from all over the world and visualizing Sutherland's location may be quite a challenge for some. See for example 1, 2 $\endgroup$ – uhoh Oct 7 '18 at 8:43
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    $\begingroup$ Thank you very much for taking the time to answer! However, I am looking for an official description of the azimuths/inclinations (which may not yet be forthcoming!) and I discussed most of your points in the original question, but thank you nonetheless! $\endgroup$ – Jack Oct 7 '18 at 22:38
  • $\begingroup$ IME, it's not uncommon for unusual mission requirements to be analyzed and approved or disapproved only upon application to the launch site. IOW, it's possible that there isn't and won't ever be an "official description" of the site's full capabilities. Rather, it's more a case of can you make a rational argument for an excursion outside of what's been done before. $\endgroup$ – RickNZ Oct 7 '18 at 22:46

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