Primarily for general aviation discussion, but other aviation topics are also welcome.
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By Rob P
This NOTAM appeared today.


How I wish the 'Radar View' actually showed the 'cone' :D

Rob P
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By PeteSpencer
Of course its not just the jump aeroplane clawing its way skywards or the meat bombs dropping at terminal velocity you need to be aware of:

During my weekend coastal bimble, having heard the paradrop aircraft in the air working Norwich I elected to pass well east of Beccles (offshore and well downwind actually) as he ran in for the drop:

I was glad I had switched to a Traffic service from Norwich as the aircraft stood on its nose and dived groundwards in front of me , hell bent on picking up more bombs.

More a 'dome' than a cone...................

Edit for clarity.
Last edited by PeteSpencer on Tue Jul 14, 2020 12:50 pm, edited 1 time in total.
By Boxkite
Probably quite difficult to parse that info to produce the 'inverted wedding cake'. Unless it was done by hand. I am sure Skydemon would have done that if the period had been for more than one day.
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By RisePilot
For reference and understanding of skydiving operations, following are some general notes as skydiving has progressed quite far from what the average forumite here understands it to be.

Long gone are the days of just flat-flyers going straight down and opening round parachutes with limited manoeuvrability.

At any given drop zone, you may have a mix of tracking jumps and wingsuit jumps. Tracking jumpers will have forward speeds of circa 50mph and wingsuit jumps have forward speeds of circa 100mph. Wingsuit flyers exit the plane on jump run (into wind and upwind of DZ) and fly along a few seconds with plane’s directions then either left/right for 8-10 seconds at 90degrees then turn downwind to fly back to drop zone – you may have multiple wingsuit groups doing left and right patterns on the same jump lift. In brief, they fly a circuit off of the line of normal jumpers. A wingsuit can easily exceed the forward speeds of many spamcans – and are particularly fond/drawn to small puffy cumulous clouds.

Canopies are deployed at 3000-ish feet for most/advanced, 4000ish for novices & 5000 for tandems. Once canopies are deployed, high-performance canopies can be dived at up to around 80mph and are extremely agile.
Last edited by RisePilot on Tue Jul 14, 2020 12:48 pm, edited 1 time in total.

What is their range from the aeroplane once they have been dropped and assuming they are all going to head back to the aerodrome at the end of their jump? Their speed may be impressive but their L/D ratio a lot less so. 1-2-5 miles?

I always give DZs as wide a berth as possible but especially so into the upwind area as I suspect few will venture far downwind from the airfield. Is that a correct assumption?
IIRC the 'cone' NOTAMs started to appear after a topic here where - 'Of course everyone knows to keep well away especially upwind' - was a subject of discussion.

I'll leave PaulS to find the thread in the archive.
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By rikur_
RisePilot wrote:For refence and understanding of skydiving operations.....

Very helpful thanks.
To what extent does the annotation on charts fairly represent the area of activity?
For example below for Bridlington - I will often be quite close to the circle shown on the chart ..... but with the sort of speeds you mentioned, perhaps I should be expecting to encountered them outside that area?
I'm typically 3000ft - 4000ft, so sounds like the cone is narrowing at that point?

[Edit: Crossed with FD]
By Lefty
This is one of my pet gripes.
1. I don’t see why parachute centres think it is ok to NOTAM huge areas of our sky as (effectively) CLOSED when most sites are only used a few days per YEAR (But the airspace is NOTAM’d all year round. We get inconvenienced 365 days per year, just in case they chose to operate perhaps 20 days per year.

2. If they are going to block off this airspace, then I think it would be only fair and reasonable for each parachute centre to man a radio so that aircraft wishing to transit the area can call to get an update on whether or not the site is active - and where the jump plane / jumpers actually are.
If they are not operating at that time,, the airspace should be open to all to use.

When I’ve raised this in the past, they say the operate on such tight margins that they can’t afford a person to man the radio. However these are quite large scale commercial operations - and to the best of my knowledge, they usually have a jumpmaster on the ground. Why couldn’t he /she respond to transiting aircraft?
Rob P, Dave W, Tim Dawson and 4 others liked this
It’s not too difficult to find out which ATC your local jump sites work and listen out on that frequency : You can even ask ATC if they’re active if you’re nearby .

Same info can be obtained with a little more effort if you’re planning on passing an en route para site.

Peter :wink:
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By Rob P
We know that is possible.

But why should we have to for something infrequent? This is the excellent point John was making.

Rob P
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By AndyR
Takes us back to NOTAM and their inefficient use. They should only be issued on the relevant days of operation. Or, in a similar vein to gliding sites, one can, I believe, safely assume they are inactive on blowy, wet autumnal days.

To those in the know, what makes it an undroppable day?
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By xtophe
AndyR wrote: gliding sites, one can, I believe, safely assume they are inactive on blowy, wet autumnal days.

Wet yes, blowy not necessarily. Always trainee to train and pilots keeping current.
And if a ridge or wave lift are accessible, windy day might see a lot of activity.
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By xtophe
Lefty wrote:NOTAM huge areas of our sky

There is no 365-days NOTAM, so I take you refer to AIP ENR 5.5.
Some entries are a bit generic. But some give you the days they are normally dropping.
And all provide phone numbers and frequencies.
Rob P wrote:We know that is possible.

But why should we have to for something infrequent? This is the excellent point John was making.

Rob P

In the case of the cousins at LKH radar you don’t even have to do that as when Chatteris are jumping they usually issue an ‘all stations’ broadcast just before the drop