Notam 30 05 2020

[Buff52]

Over FL700 that's all they say

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In yesteryear it was all about getting the aircraft as high as possible as the mission was about flying a fairly straight line to take imagery of areas as far away from the aircraft as possible. You’ll see mention of rumoured altitudes now and then and yes they were higher than most would have imagined given sensor range as well as height for defence was what mattered. The reason the 70,000ft value was specifically given related back to the known capability of a Soviet-made SAM many years ago.

Today, the mission is very different. The era of one aircraft, one pilot, one sensor has been replaced with one aircraft, several sensors and a crew of 50 at the other end of a real-time data link. Now it’s about being at the right speed, getting the right mission duration from the fuel load, managing turn speeds to protect the aircraft, as well as having sufficient height to optimise collection. The higher the aircraft is, the further away its sensors might be so height isn’t always a good thing. I think all you can assume these days is that they’re above FL600.


This may be of interest to some, a few familiar faces for this who know of the U-2 family. https://youtu.be/H-ueIDV3Dro

[zero_gravity]

All the missions over the last week/ten days have been monitored via Mode Charlie.

On a couple of sorties have I seen the trace descend for about FL650 to level off at 60K however on the present mission profile all this happens at the very edge of my coverage. We used to think that Mode C was limited to FL600 for tactical reasons , but now , not so sure.

One interesting aspect is that when he departed via the more northerly route , during weekdays , you could see the bump in the trace when he hit turbulence.This seemed to be around 55,000 feet and although not confirmed it was either over a section of high ground or , as he crossed the coast.
I suspect it is the warm air convection as he crosses the edge of the peak district near to Chesterfield ,on a direct route from KEPAD to LIBSO.

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They switch that kind of thing off after about an hour from launch, so you'll probably see whatever altitude they've reached by the time they get to the pre-entry checklist. Some cockpit photos released over the years show some of the post-launch and pre-recovery checklist steps if you look hard enough.