Mysteries, Chemtrails, Aerosols :: Mysterious NZ New Zealand based Discussion Forums The strange & mysterious, archaeological anomalies, modern oddities... Current affairs, health & medical issues, Aerosol Spraying in NZ... ...and general interest: ARCHIVES
Posted: Fri Feb 22, 2008 7:36 pm Post Subject: Secret Flight Levels Revealed!!!
[uploaded, tested, no problem, decided to move files to different file folder, left scripting folder behind #-o - all fixed now... Admin]
Secret Flight Levels Revealed
We have created a video of flight level activity, covering a 24 hour period, derived from Flight Explorer as an example of actual domestic and international flight levels over New Zealand.
There has been much speculation as to the actual altitudes that, in particular, domestic aircraft fly at within New Zealand air space between major airports.
Flight levels of domestic aircraft are not normally viewable on Flight Explorer - NZ authorities have chosen not to reveal these to date as there was a concern about terrorism in the wake of the September 11th incident. We do hear from a source however, that it is under consideration. Fortunately, we have been able to acquire this example (at great expense :) ) to end the speculation and so that Hector's contrail analysis charts can be better interpreted.
The domestic flights predominantly range from around FL250 feet to FL370 feet in New Zealand airspace. The occasional international flight over the Tasman can be seen to reach 40,000 feet (FL400).
The video covers a period between 1pm Saturday January 17th and 1pm Sunday January 18th 2004. Because this reflects a time period approximately 4 years ago and to ensure that our video reflected current protocols we checked on this and received the following reply from an authoritative source within Civil Aviation, who verified that nothing has changed since the date of our video:
Quote:
"Internally for short hops like Wgtn-Chch it is more likely to be
FL230-FL250, Akl-Wgtn FL310-330, Akl-Queenstown FL350/360.
A private jet with no great load might get up to 390-410 Akl-Chc."
It will be seen that flight levels over and near the New Zealand land mass above FL400 are quite rare, although they can sometimes be seen over the Tasman. What this demonstrates is that the higher altitudes expressed on Ross Marsden's (Hector) contrail analysis charts can basically be ignored with respect to observed contrails left by normal commercial flights.
The video shows an unedited 24 hour period,. We have speeded up playback by about 66 times and cropped the overall Flight Explorer view, both to reduce the resulting file size. Every flight in that 24 hour period is shown, although it has been filtered to hide all non-jet low altitude traffic eg. turbo props, aero club planes and the like - anything irrelevant to the formation of contrails.
The controls allow you to pause the action to see the flight details clearly, and the progress slider of course can be moved backwards or forwards to rewind or fast forward to a particular place in the action.
The airlines have been colour coded to make interpretation easier:
Air New Zealand: silver
Quantas: red
Freedom Air: yellow
Singapore Airlines: gold
and so on...
On the information bar at the bottom, the planes info (example: 24/4060) refers to the total number of planes over NZ at the time, including hidden planes and the total number in all of FE's coverage (which includes the USA as well). Current time and last update are self-explanatory.
The aircraft information depicted is as follows:
Airline/flight number
Altitude/speed in knots
Departure point/Destination
Aircraft type/ETA
Sometimes a trail behind an aircraft is somewhat irregular. And sometimes an aircraft may seem to remain stationery for a period, especially over the Tasman.This is an FE glitch and nothing to do with the video capture itself 8)
Apologies to those on dialup, although it should stream OK - the file is around 30mbs in size.
We are interested in our forum members' feedback on this. We intend to make it available permanently from our Flight Vector map resource page, as it is a good accompaniment to the map itself.
Flight levels of domestic aircraft are not normally viewable on Flight Explorer
Yes that is so
An explanation from the Airways contact as to why the height is not displayed for domestic traffic over NZ within F Explorer was as follows
As stated
Quote:
Flight Explorer first got the New Zealand data at about the time of 9/11. Consequently a conservative approach was taken to exactly what data would be provided. Sensitive data is filtered too.
That is not the only reason. In some areas in New Zealand the update of cleared flight level is handled differently by controllers - therefore the 'cleared level' would be confusing, and it was decided that the level simply be set to '000'.
You are not alone in asking. It is early days yet, and I can't promise anything, but we are trying to come up with a solution that will keep all parties happy and enable us to 'turn on' the levels.
I have also asked for clarification of the following
Quote:
When observing F Explorer the reported height does not appear to change i.e. when they come into land or take off the height doesn’t seem right
His reply to that was
Quote:
Actual Flight Level (AFL) is probably obvious; Requested Flight Level (RFL) is what the pilot has asked for - in the flight plan or updated directly to ATC; Cleared Flight Level (CFL) is what the aircraft is cleared by ATC to operate at - so these three can all be different. On FE we have a combination of AFL,and CFL being provided by different sources. When you see an up or down arrow, it is indicating the level the aircraft is operating at some intermediate level (not RFL).
Funny thing though is that when you observe the aircraft that are over the USA you see height pretty much all the time and it changes as well. It actually appears to be the height the aircraft is at.
I mean like you can see the decreasing altitudes for landing and the increasing altitudes when taking off.
We don't see this with the NZ aircraft within F Explorer.
I have been observing FE on and off since... (just looked at old emails and I see I first subscribed back in August 2006) .
When I look at the altitude info dispayed in the id tag the following applies (taken from the help section of FE)
Quote:
Aircraft ID: Aircraft identifier. Clicking on the small arrow button next to this field will display the Lookup / Go to dialog box, with information about the airline/company this aircraft belongs to.
Altitude: Altitude of aircraft in hundreds of feet. ‘T’ = temporary altitude, ‘C’ = Mode C altitude, ‘B’ = Altitude range.
### - This is the aircraft’s assigned altitude. This is reported if the mode C altitude reported by the aircraft’s transponder is less than 200 feet from its assigned altitude.
###C – This is the mode C altitude reported by the aircraft’s transponder. This is reported if the mode C altitude is more than 200 feet from its assigned altitude.
###T - This is an altitude that an aircraft has been cleared to; it is proceeding toward this altitude but has not yet reached it. It might be given a series of temporary altitudes.
###B### - The aircraft is assigned a block of altitudes; the first given is the lower altitude and the second is the upper, where the upper and lower limits are allowed.
OTP/### – This is an on-top clearance. The flight can, within certain limits, be anywhere at or above the specified altitude.
I have asked for confirmation by the chap at Airways about the altitude info for NZ again just to be clear
Also of interest is what is the max altitude that I have seen on F Explorer
Well without the domestic heights being displayed for NZ this is pretty hard to say.
What you can see though is the height info for pretty much everything else in the world (the countries that supply the data to F Explorer that is) and this I can comment on
An e.g
I am at looking at FE while typing this post and at the moment there are over 5000 aircraft in the air around the world
I can use filters within FE to modify what I can see.
I filtered out all aircraft with a reported FL of 40000 ft or lower from the picture and I see that there are 71 aircraft that are at 41000 ft or higher (none are over or near NZ, remember the international flights in and around NZ do display the height info)
I then set the filter to 43000 ft and I see the figure drops to 7
Only 7 aircraft at this time in the world who report to FE (which as said before the USA are a major player) are above 43000 ft
All are of the business jet variety (for eg qty 1 Learjet 3, qty 1 Cessna Citation 10, qty 1 Astra 1125 and the rest are Gulfstream 4 or 5's)
No commercial jets of the 747, 767, 777 etc etc seem to fly that high.
This is consistent with my own observation over time, that is it is very rare to see anything over 41000 ft and when you do they are mostly business jet type aircraft.
