restrictions related to altitude, or QNH, QNE

Kimis · Post by **Kimis** » Wed Oct 24, 2007 7:57 am

Hi to all,

Haven't found such discussion here, and hope it could be actual not only for me.

Few times I’ve got penalties for overspeeding bellow FL100 (10000ft) and landing lights on above FL100 (10000ft) then I was 100% sure, that my speed was lower and lights was off at right altitude.

I’ve noticed, that client reading altitude not from plane’s altimeter and not consider to pressure settings on it.

I’m a real pilot and try to fly at FS as real as it gets. I’m switching between QNH and QNE according to charts, and at most countries transition level/altitude is near FL65/5000ft (I’m sure you know terms). FS, unfortunately, has it at FL180 and there is no chance to change it.

So, what does that mean. Lets say I’m departing at airport in center of depression (cyclone) where QNH is 960hPa. After reaching transision level I’m seting altimeter pressure to ISA (1013,25hPa) and climbing to FL100. Here I’m switching landing lights (company policy). Plane’s altimeter here show 10000ft, but FS will show, and client will read 11431ft !!! and of course I’ll get landing ligts above 10000ft penalty.

After flight I’m approaching destination, where QNH is 1030hPa. Near FL100 plane’s altimeter is still at QNE pressure (1013,25hPa). I’m reducing speed below 250kt, switching landing lights on, and continue descent. But, at such pressure FS will give and client will read 9541 ft altitude, 460 ft below speed limitation !!! And again I’ll get penalty !

I appreciate flynet authors for their job and really understand how difficult is to program client to control everything and to take such things into consideration. But if we could expect such changes in some future version, lets say 10.6.3b, it would be great !

Post by **Konny** » Wed Oct 24, 2007 11:55 am

Hm, I'm nearly 100% sure that the clients reads the QNE value for the landing lights check. Otherwise I wouldn't call it FL100 but 10000ft. So actually you shouldn't have any problems in europe because you have to switch to QNE above 4000-7000ft everywhere. The only problem I see is when flying in USA/Canada where the transition level/altitude is at 18000 feet...

Kimis · Post by **Kimis** » Wed Oct 24, 2007 12:24 pm

maybe problem is only on PMDG products. When I'm reaching transition level, I'm just pressing "STD" button on main panel and not changing pressure value, as I even do not see it. Most probably that is a problem why I'm geting penalties

I remember same problem was with FS Passengers program.

flightsimer · Post by **flightsimer** » Wed Oct 24, 2007 2:18 pm

kimis, its funny you brought this up... i was wondering the same thing 2 days ago. when i was looking through transition levels in different countries. is it possible to get the transition levels set to the real world as to fl100 for all the countries? And i to had those penalties when i shouldn't have, but I've also been getting the taxiing above 25 kts when i was taking off. I know that u have 40 seconds i believe it is to get into the air after you go over the 25kts, but im normally off in about 20, so i was under the time limit but still had been getting the penalty...

Kimis · Post by **Kimis** » Wed Oct 24, 2007 7:37 pm

I have to agree to remark about different TL/A over USA, and probably Canada. I've got penalties during flights over Canada, but never over Europe, as far as I remember. If client is sensitive to USA/Europe TL/A, than it's great. I confess that I used common European TL/A

flightsimer · Post by **flightsimer** » Wed Oct 24, 2007 11:11 pm

i was just doin a cargo flight to klax from kpit.... i was decending down... 30+miles out at fl120... so i increased decnet rate...
i was coming over a mountain, and then it happened... ding, i hear the client, i see up top "co-pilot, check ur landing light on" that made me so mad...
is there a way that this can be prevented, especially when klax is at sea level, so i shouldn't of got the penlaty...

IslandBum · Post by **IslandBum** » Wed Oct 24, 2007 11:26 pm

Flightsimmer

If you look at an LA Area chart - there is terrain on 3 sides of the airport with 30 miles - normal (RW) procedure dictates
(depending on which direction your coming from that you descend below 10000 feet after Riverside - whne i operate into
any of the LA Basin airports I tend to fly that way - in this case Flynet is perfectly correct -

Leif

flightsimer · Post by **flightsimer** » Wed Oct 24, 2007 11:48 pm

i was coming out of fl120, i just passed fl150, so if i would of turn them on i still would of been penalized because i was over fl100. if i was at below 1000 ft above the ground then yes, but if im 30 out and fly over a mountain, why should i be penalized?

IslandBum · Post by **IslandBum** » Wed Oct 24, 2007 11:59 pm

The mountains go up as high at 11000 feet there ???

Leif

flightsimer · Post by **flightsimer** » Thu Oct 25, 2007 12:13 am

i was just flying over the peak, and the mountain was starting to go down to sea level. i was just passing through 11000 ft when i heard the bell, cause i looked up to see what my altitude was, and it said 10934, and thats why i it supprised me... take 1k off of 10934 would be 9934 since the penalty doesnt happen until ur 1k ft above the ground, and that sounds right.

CAPFlyer · Post by **CAPFlyer** » Thu Oct 25, 2007 12:20 am

Because it's impossible for the system to determine if the reading of 1000AGL is due to a mountain or due to the ground coming up to meet the airplane or the plane diving to meet the ground. There are hilltop airports that have very steep drop offs just before and just after the airfield itself, so any algorithm that uses rate of change to the altitude to determine whether or not it's temporary or not won't work. The only thing I can think of is to disregard any momentary reduction of the altitude below the allowed altitude, but then again, unless it's an extreme circumstance, there is not normally any reason to pass within 1000 feet vertically of a mountain top during approach while flying an airliner. All charted approaches are designed to maintain at least 1000' separation from terrain during all portions of approach due to the possibility of barometric variance between the reporting station and the aircraft's location.

flightsimer · Post by **flightsimer** » Thu Oct 25, 2007 12:54 am

i didnt know that i was gonna be within 1000' of it, at that altitude in the La area. I was flying in the VC so i didnt know that "i was that close to it". wat happens when the airport is above 9000, 1000ft above agl would be 10000? if u put on the lights then u gonna get penalized, if u dont ur still gonna get penalized.

Stan · Post by **Stan** » Thu Oct 25, 2007 1:38 am

Quote"there is not normally any reason to pass within 1000 feet vertically of a mountain top during approach while flying an airliner."
Wish i could tell Microsoft ATC the above because they always vector me straight into a mountain while on approach to Alicante runway 10.It must be because i have got FSTerrain installed.Luckily i am aware of this and always delay my descent until i have passed over this mountain top.

flightsimer · Post by **flightsimer** » Thu Oct 25, 2007 2:07 am

Stan wrote:Quote"there is not normally any reason to pass within 1000 feet vertically of a mountain top during approach while flying an airliner."
Wish i could tell Microsoft ATC the above because they always vector me straight into a mountain while on approach to Alicante runway 10.It must be because i have got FSTerrain installed.Luckily i am aware of this and always delay my descent until i have passed over this mountain top.

i know... they do it to me at.... damn i cant remember the code or name, its in north carolina and is 80 some odd mile away from KCLT. anyways it sits right in between 2 small mountains. but the one time they had my down to 3500' i believe, and the mountain peaks were arround 5500'. something like that... but there wher low clouds, and limited visibility, and i fly into a cloud then BAM! right in front of me is the mountain... i was lucky i was flying a 757 with rolls royce engines... damn those things are powerful... but u would think Fs wouldnt have those types of glitches, after doing this for what? 15 years now?

Kimis · Post by **Kimis** » Thu Oct 25, 2007 10:27 pm

I've been penalised same way, flightsimer, just few minutes ago

Just had nice VFR flight from WA to ID over nice valleys of Rocky Mountains. come clifs were closer than 1000 ft and I of cource didn't had landing lights on

And I flew not an airliner. it was small Baron 58.

I understand, that it is to difficult for system to recognise was it just an clif of mountain, or that was intention to land.
But maybe system can consider few factors at once, like altitude AGL and MSL and elevation of destination airport, or elevation of airport where pilot has landed after violating 1000AGL rule?