PPRuNe Forums - View Single Post - SkyDemonLight & airways inaccuracies ?
View Single Post
Old 24th Apr 2011, 17:29
  #11 (permalink)  
tdbristol
 
Join Date: Oct 2006
Location: Bristol
Posts: 117
Likes: 0
Received 0 Likes on 0 Posts
Parts Class A areas shown on SkyDemon Light not on CAA chart

Quote:
there are lots of other areas of airways on SkyDemon which are not shown on the current CAA chart
Could you list them? These need pointing out to the people that produce the 1/2 and 1/4 mil charts as a matter of urgency IMHO
I don't think I can list them all - it would require lots of plotting of different routes, perhaps at different heights, but there seem to be quite a few on quick looking.
I have looked a fair mount at the route I plotted (EGWC Cosford to EGCJ Sherburn at 5,000') and there seem to be 4 on this alone:
- L10 just south of the route near Cosford from 4,500' [v. small part]
- L8 north of the route, ~10nm north of Cosford
- M605 from 4,500', starting ~10nm on ~hdg 340 from TNT: the route infringes this
- L603 just to the west of the route partly coinciding with L975

In each case it seems that these are small corners or parts of the Class A airways that are near but just outside other CAS shown.
Anyone who knows better please correct me, but my reading of the ANO seems to indicate that all these airways are on a centreline then with a width of +/- 5nm. It seems to me that if you take the centreline alone it is within other CAS, but if you take the full 10nm width then parts of the full width lie outside other CAS.

My own guess at interpretation as to why these are not on the CAA chart [a complete guess! I may well be wrong] is that:
a) if the CAA were to add all these into the chart it would make it horrendously complex (or more so than it is already)
b) and aircraft in CAS would generally follow the centreline so are covered by other CAS [or would be otherwise in CAS]
c) so the fact that small areas of Class A are not mapped on the CAA chart and that therefore we [me included!] occasionally infringe these small corners of Class A does not pose any danger to aircraft in CAS.

Anyone else with ideas?
tdbristol is offline