Altimeter full real.
 

For the full real pilots:

Let's assume this: the dynamic weather works. Air pressure changes while clouds are forming over the channel and we're waiting for a gap in the overcast.
For the mission we've set our compasses and aligned the gyro.

But we've also got the altimeter that can be set to the pressure, where can we find the right settings for the field or must we just zero it before take off? And do we bother at all?

S!

Actually the tower should give you the pressure when taking off and landing.

It's possible to change..so does it have a real function? Currently it's for AGL use only..if you want to do so. I haven't heard them calling out the pressures.

tower usually has to say QNH. i always cheated since i knew already what altitude the runway was, so i just set the altimeter to that.

You could always just do a VFR landing. I got out of the habit of using the altimeter back in il2fb and just never really got back into it again. Unless the weather conditions are downright miserable I can't imagine it'd be necessary.

But then again I don't generally fly bombers.

I think you will find the Brits to use QFE as a general rule.

We certainly do and still do.

I set QFE. I have also been flying on the ATAG server and was very pleased when it went dark!!! I came back in a couple of hours later and it was truely dark (nice to see all the correct constellations as well, in about the right place and not just a ramdom star field). I needed QFE to give me an even chance of getting on deck back at Ramsgate. I did and landed on a very dark runway.

pupo162
How do you know the Airfield Altitudes?
I have been working from a modern chart. For those airfield no longer in use I have been flying from them to either a field I do have the height for or ditching to get sea level. I also think the Sea level pressure varies across the whole map as there are inconsitancies with this method. Also I think the pressure changes with time. I'd be very keen to know what is happening.

Here's a thought:
There is a mechanism for the Fighter Controller to report enemy aircraft. So the game is detecting aircraft and responding with information. What if the game detected the presence of freindly aircraft within 2miles and 3000ft of an airfield and reported local wind and pressure be it QNH or QFE.

I have been compliling an enroute Supplement (only started a couple of days ago so it is not complete) here: Enroute Supplement - Channel

Gosling
VBF-12

"Here's a thought:
There is a mechanism for the Fighter Controller to report enemy aircraft. So the game is detecting aircraft and responding with information. What if the game detected the presence of freindly aircraft within 2miles and 3000ft of an airfield and reported local wind and pressure be it QNH or QFE. "

I don't think it matters one bit if its QNH or QFE wrt to bandit Altitudes. The early CH height fiinding was very basic arrangement and not very accurate at all. Certainly not within the difference that might be caused by using QFE or QNH as a reference :)

Oh sorry - I wasnt critising the Radar. I was suggesting a way the game mechanics could be modified to allow ATC calls to returning pilots. Sorry for confusion.

Gos

So setting the altimeter while on the airfield is a bit too rough? What did they had in mind when the option was made available?

i only flew on 1 airdrome, so it was always the same.

Don't need any altimeter settings - just dial in the airfield altitude on the altimeter before take-off and you automatically have set QNH (barometric pressure at sea level).

Yep as long as you know the Airfield altitude :) .... where do you get that from ?

Other option might be the Mission file if Mission pressure is stored in there ?

Interesting point. None of the comms report a pressure to use on the altimeter pressure scale so it seems to me like vertical navigation is not modelled correctly. I can therefore only assume that reported altitudes are QNH, i.e. above sea level and that there are no regional differences in QNH. Having said that, dynamic weather has not been integrated yet so this may all change.

I do not understand. Bokin please try to explain it.

Regards Varrattu

Think I was a bit quick of the mark with that last comment. I don't think I made sense either! :o

All altimeters are calibrated through the pressure setting... so yes they do have a scale... but I've noted that to adjust them to read zero on the airfield the pressure setting has to be down around the 980mb level and doesn't change much.

If your flying around in real airspace its important that in order to ensure safe vertical navigation the other people around you have their altimeters calibrated the same as you, i.e. they are using the same pressure setting. Generally, around an airfield you would be provided with a QFE pressure setting. Putting this into you altimeter would mean that it would read zero when your on the airfield.

When you leave the airfield airspace you generally change the pressure setting to QNH. This would be given to you over the radio and would mean that your altimeter would read the altitude above mean sea level. As pressure is a variable, QNH pressures differ by regions.

Finally, when flying above what is known as the transition layer the altimeter pressure would be set to 1013mb - and your height is translated as a Flight Level.

Point I was trying (but failed) to make was that there are no pressure settings given over the comms so to me it seems somewhat irrelivant at the moment to start adjusting the altimeter scale.

Thinking it through... there could be some testing done here to deterime at what heights the radar reports bandits are at and then adjusting the sub-scale to see if it using Flight Levels?

@Bonkin & @cheesehawk

Thanks for the clarification. ;)

Varrattu

Are you sure about this Cheesehawk? Does it apply to AI also? Historically of course we had radar and the Royal Observer Corps. The latter dotted around the coast would attempt to confirm e/a type, numbers and height as raids came in. Seems a bit odd (in the game) that in order to get a radio report of enemy location they have to be spotted (or in the same area) as one of your own aircraft (or AI?) in the air?

I don't know the answer to this - but again, for safe vertical navigation for aircraft in the circuit I suspect they did. The control towers were there for that very reason - control. In the real world when joining an airfield control area you are given the QFE, runway in use and wind. I don't imagine it was any different back then.

The best guess we (of the virtual 322) could make about the altimeter is (currently) that the altimeter would be setup above sea. Sealevel plus approx 100ft. Sadly setting up the altimeter could be the cause of some crews to crash doing it.

Thanks for sharing your work on this, much appreciated.

Chin chin

Great stuff. What are you using for your altitude information though ?

Something like this I guess?

http://www.raf.mod.uk/raflyneham/raf...55130C1227.pdf (opened on 18 May 1940 as Number 33 MU).

They speak of pression regions. This refers to Altimeter Setting Regions (ASRs). The QFE (Field Elevation) is for the field reading only. So indeed VBF-12_Gosling's, Enroute Supplement - Channel, is handy for the fields on approach and operating (thank you for those!). Most of the time (nowadays) the standard pressure setting 1,013.25 [hPa] is used for transits on flightlevel. Imho when running a dedicated server (and for the die-hards) it could be the case that the settings are given in a briefing. On deciding the field the pressures are given and the pilot takes note.

And for those that can't be bothered with setting up the gyro's compasses and altimeters.. ..

You could also have a read on the NATS website... checkout http://www.nats-uk.ead-it.com/public...Itemid=11.html and scroll down the page until you find "Altimeter Setting Procedures". This explains how it should be done today.

Also look at the links on the left hand side. You can select "Aerodrome Index - Specific" and for those airfields still active, i.e. Biggen Hill, pull up the aerodrome chart. Biggen for example, has an elevation of 599ft amsl.

Indeed a good read. I don't know how much the methods differ from the RAF during WW2. Multiple sources give opposite answers (crews pilots). I'm aware that we don't fly software as FSX etc and most won't bother and just spend some ammo on targets, i find it interesting to 'fly' the Cliffs as the original crews and pilots did as far as ingame realism lets me.

How 1C imagined this is one of my questions.

For every flight / take off the REICHSWETTERDIENST prepared a weather forecast for start location and destination. Also included was the QFE for departure aerodrome and destination aerodrome. For this they used the form --Vordruck RWD F2--.

Source: Der Flugbetrieb der Luftwaffe, L.Dv.5/1Regards Varrattu

I haven't got CLOD yet (waiting for a PC that will run it) but one thing that won't have changed in the last 71 years is terrain elevation so I guess I'll check out airfield elevations via any modern map - perhaps Google Maps or something similar will give elevation info for those not resident in the UK? It doesn't need to be exact since baro pressure is constantly changing anyway. I've also got old aviation charts lying around.

Interesting test.

You can determine the exact elevation in metres using FMB. Place an object on the ground then read the Z co ordinate in the bottom left corner. Using this you can determine each airfields elevation. If you park your aircraft on the ground and set your altimeter to the exact known altitude you then automatically have the correct atmospheric pressure (QNH) for the map.

Here are all the UK airfield elevations obtained from QMB and verified in game. I will compile the whole lot into a single PDF once all the data is in. Apologies to the French if the spelling is a bit off :)

IL2 STURMOVIK CLIFFS OF DOVER AIRFIELD ELEVATIONS

UK AIRFIELDS
Bembridge 13m 43ft
Biggin Hill 179m 587ft
Boscombe Down 127m 417ft
Canterbury 51m 167ft
Croydon 101m 331ft
Eastchurch 7m 23ft
Farnborough 77m 253ft
Ford 1m 3ft
Gatwick 60m 197ft
Gosport 1m 3ft
Gravesend 63m 207ft <<< Edit
Hamble 20m 66ft
Harewell 120m 394ft
Hawkinge 158m 518ft
Heathrow 23m 75ft
Hendon 50m 163ft
Heston 30m 98ft
Hornchurch 10m 33ft
Kenley 174m 571ft
Larkhill 114m 374ft
Lee On Solent 10m 33ft
Littlestone 22m 72ft
Lympne 100m 328ft
Maidstone 84m 275ft
Manston 44m 14ft
Netheravon 119m 390ft
North Weald 80m 262ft
Northolt 37m 121ft
Old Sarum 79m 259ft
Portsmouth 1m 3ft
Ramsgate 47m 154ft
Reading 46m 151ft
Redhill 24m 79ft
Rochester 130m 426ft
Rochford 10m 33ft
Ryde 52m 171ft
Salisbury 131m 430ft
Sandown 21m 69ft
Southhampton 9m 30ft
Tangmere 12m 40ft
Thorney Island 1m 3ft
Upavon 147m 482ft
Watchfield 100m 328ft
West Hampnett 21m 69ft
White Waltham 36m 118ft
Willimington 22m 72ft
Yatesbury 170m 558ft

FRENCH AIRFIELDS
Abbeville 61m 200ft
Achiet Grevillers 127m 417ft
Amiens Allonville 89m 292ft
Amiens Glisy 59m 194ft
Aras St Liger 109m 358ft
Arras 98m 321ft
Audembert 42m 138ft
Barly 122m 400ft
Barly 112m 367ft
Beamont Le Roger 139m 456ft
Beauvais Nivllers 120m 394ft
Beauvais Tille 99m 325ft
Berk 1m 3ft
Bernay St Martin 161m 528ft
Bolsjean Ecuires 57m 187ft
Brias 150m 492ft
Brombos 191m 627ft
Bulougne Alperch 69m 226ft
Caen Carpiquet 61m 200ft
Caffiers 112m 367ft
Calms Marck 2m 7ft
Carquebut 20m 197ft
Champ Les Guines 75m 246ft
Colembert 198m 649ft
Coquelles 13m 43ft
Cramont Yurtench 121m 397ft
Crecy 141m 462ft
Creil 101m 331ft
Crepon 59m 194ft
Deanville St Gatien 140m 459ft
Desures 200m 656ft
Dieppe 101m 331ft
Estree 80m 262ft
Grandvilliers 180m 590ft
Guines 46m 151ft
Haute Fontaine 180m 590ft
Horm Elingen 161m 528ft
Hydrequent 78m 256ft
Le Havre Octeville96m 314ft
Le Touquet 1m 3ft
Licescourt 70m 230ft
Marquise West 24m 79ft
Merville calonne 9m 30ft
Monchy Briton 150m 492ft
Montdidier 108m 354ft
Oye- Plage 2m 7ft
Persan Beaumont 42m 138ft
Peuplinguess 101m 331ft
Pihen 96m 315ft
Plumetot 40m 131ft
Poiy Nord 171m 561ft
Querqueville 1m 3ft
Rezy Norrent fontes 94m 308ft
Rosieres En Santifer 82m 269ft
Rouen Boos 140m 459ft
Roye Amy 83m 272ft
Samer 61m 200ft
Sempy 120m 394ft
St Inglewert 129m 423ft
St Omer Arques 29m 95ft
St Omer Clairmarrias 9m 29ft
St Omer Wizennes 78m 256ft
Theville 135m 443ft
Tramecourt 126m 413ft
Wailly Beauchamp 51m 167ft
Wissant 21m 69ft
Yvrench 110m 361ft
Zuterque 36m 118ft

SC/JG_Ivank Oct 2012

PDF of the list in Post #35

http://forum.1cpublishing.eu/showpos...8&postcount=35

Guys (Cheesehawk and IvanK), thanks for the explanation and effort that you've put into this.

When the dynamic weather is fully integrated I'm looking forward to seeing where it takes us. I like to fly full real and am hoping that we'll have to take account of pressure settings for navigation and finding the enemy. I also imagine that knowing the height of an aerodrome above sea level might be useful for high level bombing - but currently that's a whole part of the game I've yet to look into.

No Gravesend in the list?

Still, I understand it's too risky to bomb, what with No.501 County of Gloucester being stationed there :D

Here you go in attached zip a PDF Gravesend included. Revised Formating as well.

It would also seem that the QNH varies with the time of day. Thats what I am seeing on the ATAG server anyway.

It very much depends what we're doing.

Gliding, I'll just zero the altimeter as part of the pre-flight checks. This isn't necessarily going to be the same as QFE because QFE is updated in discrete intervals along with the ATIS (though one generally doesn't fly gliders from somewhere which has an ATIS).

But looking at it another way, if you set QFE in a powered aeroplane, you won't necessarily find the altimeter set exactly to zero when you're sat on the tarmac, because real objective of the exercise is to make sure that everybody is at the same height in the circuit so that they can all see each other, and nobody descends onto anybody else's head. Assuming about 30'/mb, and a rate of pressure change of about 1 mb/hour, you might get a 30' error relative to the ground, which is quite acceptable for visual flying. But this means that QFE isn't the same as simply zeroing your altimeter on the ground.

Powered, I'd be inclined to use QFE for flying in the circuit, but otherwise, it makes pretty good sense to use QNH, not least because the regional pressure setting is a QNH.

In the end, this is just a function of the fact that the maps are made by reference to mean sea level as a datum line, because it's effectively universal.

Earlier today I was flying aerobatics in a Bulldog with the altimeter set to QNH for the entire sortie from engine start to engine stop. The obvious advantage is that you don't have to worry about making a mistake when switching between QNH and QFE or vice versa.

Resurrecting and old thread but thanks for the list IvanK - just what I was looking for!

Chaps

I have gone a bit further with my Enroute Supplement. 616Sqn now has a Flight Planning Office:
616Sqn Flight Planning Office

There is a fair amount of useful information in the website as well.

Its still not quiet fininshed and there are a few more runways to enter etc...

The lower charts are clickable for printing too.

Gosling
Lt RNVR
616Sqn

Interesting read...
 

I really need to get into the details of all this stuff :P (considering ive just purchased xplane 10 and looking forward to microsoft flight) get myself a few aviation books, better controls etc.

Anyway at the moment im trying to get the hang of bombing (in the Blenheim) and i now assume that the figures above (Height differences) also play a crucial role in bombing?

Atm i have created a simple practice bomb route via multiplayer (see attached mission) with a blenheim & he111 @ 10000ft (roughly) and another blenheim @ 19000ft (roughly). So far using the calculations given to me from BlackDog (Thread title - Work out TAS from meters? For bombing) i still appear to be bombing short from the target. So my question is?

a) Should i create a mission where i take off from an airbase? (where i can set the correct altitude)

b) Since my target is Le Touquet airfield, would i need to add/ subtract the difference in altitude? would this make a big difference?

Other than that. I hope in the future that the full mission builder could have both FT/KM and MPH/KPH for the different armies rather than just the 'German' unit measurements

Ross

Sorry missed of my mission - to play via mp.
 

Ross

Success
 

Did a small test and i managed to hit more or less on target

Will explain later on in the next few days

Cheers

Ross

Yes, please share. I think many of us are waiting for the patch and hoping it brings bombing goodness! At the moment it is harder than it should be.

I think going above 5000ft with the Blenheim is going to stretch it a bit. It has no autopilot and the higher you are, the harder it is to align the target because the cockpit framing obstructs the view out ahead: by the time you can see the target, the higher you are the less time you have to align it.

It could be possible to bomb from 10000ft or so but you would need other people with you to bomb as a group and saturate the area, as it's not that easy to hit right on the bullseye any more.

As for the altimeter differences, for optimal results yes, they should be taken into account.

What you need to bomb accurately is:

1) Your GS (speed relative to ground): This is indicated (IAS) converted to true (TAS) airspeed at your current altitude and then also corrected for wind. For example, if your TAS is 250mph but you have a 20 mph headwind, you GS is 230mph.

2) Your altitude above the target: This means you need to know your altitude above sea level and the target's altitude above sea level.


So, if i'm flying at 10000ft and bombing a target that is on a hill 1500ft high, i will calculate and use a TAS value for 10000ft (no idea what we can do about wind yet to get GS in the non-automatic sights), but the altitude i will input on the bombsight will be my altitude - target's elevation = 10000 - 1500 = 8500ft.

;)

If the weather goes dynamic you can still use the "basic tools" for bombing: a map, and the stopwatch. From your direction and the IAS, and from your path you can calculate the wind, the GS, and correct your path.
Height is not so easy to figure out if the pressure is changing, but ground objects, roads or areas has a length and with on the map and in the sight. The scale of them gives the AGL.
Of course there could be different wind layers with wind effect on the falling bombs so nothing could guarantee the perfect hit!

Will the dynamic weather have this huge impact on the accuracy of bombing?

Main purpose of the altimeter was so to set it to the elevation of your destination airfield in RL (for obvious landing purpose). That value is listed on your chart along with other information about the field.