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MikkOwl
03-18-2010, 04:04 AM
1: NAVIGATION RESPONSIBILITIES

In aircraft with more than just the pilot, did the other guy(s) ever do or help out with the navigational duties? In medium and large bombers, obviously they had the responsibilities of navigation, but what about the smaller ones? IL-2 series with rear gunner on board, Bf 110 with a bordfunker sitting around in the back, PE-2 etc.

2: HOW WAS IT DONE?

When someone other than the pilot took care of the finer points of navigation, how much did they really calculate in reality? What data did they need (both for bigger bombers, and for dual crew planes)? How fast where they at performing these calculations (for example, pilot asks range to target, or for the approximate time to target). Also when climbing, descending or turning, how is this reflected/handled in navigation, both in procedures and in calculations? The pilot says he is turning to a certain heading, or says he changed heading to newheading, how does the navigator handle that? Just assumes that the course is changed at the time new heading is established, or before the turn, or midway or what? :)

3. WHAT AFFECTS TRUE AIR SPEED IN IL-2?

We don't yet have wind to worry about in IL-2. But what things affect true air speed apart from altitude (lower pressure)? Does outside air temperature make any difference to true air speed in IL-2? When climbing up higher, does the drop in air temp additionally correspond with a difference in speed as well?


Reason I am asking

For a while I have wanted to make the rear gunner of the Bf-110 (and other planes with multi-crew) do something in multiplayer except being silent and occassionally shooting at stuff. That the speech was disabled for multiplayer sucks, and further punishes anyone thinking of not using a single engined fighter.

Then I saw the reality show "Bomber Crew" where some youngsters are trained on WW2 vintage aircraft in how to crew and successfully fly those old large bombers. The pilot in one training exercise told the navigator in the back the aircraft heading, indicated air speed and altitude, and the navigator tried to keep track of their position on the map. That seemed like it would be possible for IL-2.

Thus now I started development on a program to replicate this function. It is a navigator AI for planes with more than just a pilot. One of the benefits of not flying single engined fighters all alone.. or so it should be.

The interface is intended to be through audio completely, with him speaking to you and you speaking to him. Using the keyboard to talk to him will also work, but not as natural.

The main idea is that you tell him altitude, heading and indicated air speed (and maybe outside air temperature?) and he will keep track of what map grid you are in, distance to target, approximate time to target. Also be able to tell you the heading to air fields, waypoints, land marks or whatever.

While it would be possible to read the IL-2 realtime logs to extract coordinates of things, I don't want it, and it should not be necessary. One takes off and tells the crewmember the current location (In terms of grid - A7, numpad 5, for example) and he assumes that is the current position. The accuracy of the navigation will depend on how good you are at keeping the heading, speed and telling your navigator these numbers. He does not actually know where you are, he just keeps trying to guess it using the numbers you give him. Dead reckoning is the method used. Getting lost is just as possible as in reality - and when that happens, you have to look out the window and compare landmarks to your map, and then when you think you find out where you are, you tell the navigator what grid coordinate you think the plane is currently in and he'll make the adjustment. One can also tell him the destination grid and he can tell you how you need to turn from where he thinks you currently are.

My goal is to be able to completely get rid of the built in in flight map function of IL-2, and just use a printed paper map instead (screenshot of the map from the in-game mission builder or something so the grid matches). I'd like to have land marks (cities) and air ports be definable to the AI navigator so he at least knows where they are on the map. Could be done through config files for each map or something.

A fun feature I would like to implement (which is completely possible) is to make the navigator be aware of the clock in your plane (all planes have them), and he can use that as reference when telling you at what in-game time we expect to reach the destination etc. That would be immersive :) Have to actually LOOK at that time piece on the instrument panel for once.

I hope I can finish it and make it workable and useful. May release it if it works decently enough. It is actually not very complicated and I wonder why no one bothered with this before.. Multi-throttle that I made was much more complicated.

Range = 85 kilometers
Heading = 1 degrees
Map Grid A9, numpad 4
Altitude = 5000 meters
Indicated Air Speed = 300 km/h
True Air Speed = 398 km/h
Estimated Time of Arrival = 0 hours, 24 minutes, 48 seconds

julian265
03-18-2010, 11:20 AM
I like to fly full switch offline, with a printed map, but this would be awesome in addition!

I hope 1C is taking notice of these features for BoB, if they haven't already :)

Crew interaction is definitely a step towards reality.

K_Freddie
03-20-2010, 11:50 AM
On mission assignment:

Study Map => Take note of easily identifiable land features that'll be en-route.
Also take note of other features, should you get lost.

Ground controller is most helpfull at times - This 'all-weather guy' can see anything. :grin:

MikkOwl
03-20-2010, 01:39 PM
K_Freddie, yes, landmarks important, and pre-flight should leave room for those things. Planning the mission etc. So far making the AI navigator aware of where we want to go (a single, current destination) as well as our own present location is easy. Just tell him the grid letter, number, and then using the system people use online (dividing a big 10km grid into 9 zones), call out what 'numpad' key zone it corresponds to. The destination is set as the middle of that zone. But making him aware of everything else that is relevant is more difficult to solve in a smooth way.

Can always input the home base, other friendly air bases, maybe a couple of waypoints and a few landmarks when entering a new map and he'll remember it. But don't want to have to do it more than once for a map. Can check logs to find out what map is being played at the moment, and check what plane we are flying to figure out what 'side' airports are friendly and which are not, and then automatically remember what we taught him (by saving it automatically in a file and it being used automatically the next time the map is being played). Another possibility is more technically difficult but allows being very precise - entering the stuff oneself in an .ini text file. But seems like tedius work. Maybe mainly for landmarks rather than essential info like airfield locations.

Would be great to be able to have landmarks like big cities be referable to by their name somehow. But that wanders into the land of great complexity (too many different maps, cities and city names, which also poses extreme problems with the voice files needed and the difficulty of being limited in input - the program can only recognize keyboard keys, and since most are used for other things, the allowed keys will be limited to the numpad keys, which has to cover all communication from user to AI Navigator).

No, the system should be simple, universally adaptable to any map, and effective. The teach as you go and remember it method seems to be most practical.

No one seems to know/share anything about how real navigation was done by a navigator as in the examples I requested, but it is okay, I'll make some good guesses on how big time delay should be before AI navigator answers.

Some of the more unusual features planned include:

- (Definitely included) If using voice recognition as intended (such as using "Shoot!", which sends a keypress or series of keypresses when it recognizes a phrase scripted to it), will allow letting the AI navigator know which key is our press-to-talk key for TeamSpeak. When we are speaking to others, he will delay saying anything until we are done. If I could know if others were speaking on teamspeak somehow, I would make him shut up until they are done too.

- (Probably included) Permit the AI navigator to function only when in an aircraft with at least one more crew member besides the pilot onboard and unharmed. By reading the event logs and using devicelink as well it is possible to know this.

- (Maybe included) Fill in some of the gap from rear gunners not being able to speak at all online (an annoying unrealistic thing of MP currently, and unimmersive). Can't communicate what he sees, but can at least let the pilot know he's wounded or heavily wounded, and also comment on if a target was shot down or blown up. This stuff is visible on the hudlog and/or chat anyway so it's not cheaty, but it will be more realistic and immersive.

- (Not very likely) Possibly able to make this crewmember carry out functions that would belong to his responsibilities anyway.

- With the upcoming 4.10 patch for IL-2, we get interesting radio navigation. Triangulation is possible if knowing the bearing to any other landmark (or radio beacon) nearby. Should be able to add a function for the navigator being able to use the bearings (informed by the pilot) for these in a logical way.

Skoshi Tiger
03-21-2010, 12:49 PM
Hi MikkOwl,

Very interesting topic.

If you want to look into the role of the navigator in a bomber aircraft try to find a copy of "B17 Flying Fortress The Mighty 8th".

You can fly the whole trip from England to Berlin and back in the navigators station in real time. (Not sure if anyone has actually done it though!)

As a 'Study Sim' it's not too bad, though the graphics are a bit dated. There is also a radio compass (ADF) though I can't remember ever using it.

Cheers.