Difficulty understanding LANDING-NAVIGATION-GLIDESLOPE and needles.

[WildBillKelsoe]

Coming from Mig-21, I am confused about heads and tails on KPP compass. (yes I asked before about it but in Mig-21 subforum).

 

I will explain what I understand by each of these modes, how to mechanise them, and if I am wrong, please please correct me.

 

 

 

1)Navigation

 

is,... Navigation. Piece of cake. You use the SC knob under the KPP to punch in the required intercept heading for RSBN station. You CAN NOT use the initial heading or distance switches on the right hand RSBN channel box. If for example, Krymsk, then RSBN channel to Krymsk is 28. Dial this in, and the needle (the solid long one) points to Krymsk. The hollow shorter needle on the other end points AWAY from Krymsk.

*** needle wise, correct? ***

 

2) Glideslope

 

this is tricky... So lets suppose you are flying under the hood, or in a soup (apologies Belsimtek), you can't see scheiss. A real nightmare. But you are lucky. Under the soup is clear. at least to 600 meters.

 

You flip the mode switch to glideslope, from above the soup, from 132 kilometers out of Krymsk (our dear friend BTW), then you USE the initial AZIMUTH (nevermind distance) to set your landing direction or intercept direction (not SC knob on KPP). As a result, still our solid/hollow friend is the one to follow, not our other SC friend used in Navigation.

 

*** CORRECT ME *** but if the glideslope is used to safely get you below the soup till about 17 kilometers out, why can you change the initial heading switch? why not use the SC knob? what does each do in this mode??

 

3) Landing

 

so you're down safely below the soup, you are 17 km out of Krymsk, everything looks good, but the weather is turning bad into mist and fog (YAAAAY!!!!, not really), you flip the switch to LANDING, you set both SC and RSBN initial heading to 220 degrees (219 actually), then as you approach you start to notice only initial heading moving away from 219 (not hugging the SC needle anymore). You start to panic. Which should I follow??

 

 

So you decide to follow SC needle and regardless of initial heading slowly moving to your left, then all of a sudden, it moves real fast, yes!!

you missed the approach, dummy!!!

 

So *** CORRECT ME *** What is the manner of using LANDING mode when you've used glideslope mode and still facing course 220 and both SC/RSBN needles are hugging eachother intimately? what if you decide to play with initial heading bug? do you follow it as landing course or the SC needle course?? <--- That is the million dollars question.

 

 

Lastly, the SC needle. Which is towards (the rectangular hollow or the shorter hollow) and which is away from??

[Ramsay]

I don't know if I'm flying correctly but I'll explain how I fly and then hopefully someone will step in and correct me if I'm telling you something wrong.

1)Navigation

 

is,... Navigation. Piece of cake. You use the SC knob under the KPP to punch in the required intercept heading for RSBN station. You CAN NOT use the initial heading or distance switches on the right hand RSBN channel box.

I might use the initial heading or distance switches if I was out of range of a RSBN station - say I want to fly from Senaki-Kolkhi to Krymsk, there wouldn't be a RSBN correction signal on channel 28 because the beacon was to far a way. I'd therefore measure the bearing 305° and distance 478 km on the F10 map.

Use the initial heading or distance switches to set the RSBN needle on the RMI to point in the direction Krymsk and the PPD-2 range to read the correct distance.

Even without a RSBN correction sign the RSBN-5S will track the approximate bearing and distance to Krymsk.

Once in range of Krymsk and receiving the correction signal the RSBN-5S will read an exact distance - rather than a dead reckoning, estimate.

 

If for example, Krymsk, then RSBN channel to Krymsk is 28. Dial this in, and the needle (the solid long one) points to Krymsk. The hollow shorter needle on the other end points AWAY from Krymsk.

*** needle wise, correct? ***

Yes.

The long thin end of the RSBN needle points in the direction of the RSBN transmitter and the end with a round loop, points away.

The long end of large double line course needle points along the desired ground track - so towards the RSBN transmitter if flying TO, or away if flying FROM.

2) Glideslope

 

this is tricky... So lets suppose you are flying under the hood, or in a soup (apologies Belsimtek), you can't see scheiss. A real nightmare. But you are lucky. Under the soup is clear. at least to 600 meters.

 

You flip the mode switch to glideslope, from above the soup, from 132 kilometers out of Krymsk (our dear friend BTW), then you USE the initial AZIMUTH (nevermind distance) to set your landing direction or intercept direction (not SC knob on KPP). As a result, still our solid/hollow friend is the one to follow, not our other SC friend used in Navigation.

 

*** CORRECT ME *** but if the glideslope is used to safely get you below the soup till about 17 kilometers out, why can you change the initial heading switch? why not use the SC knob? what does each do in this mode??

Tricky question to answer, I'll do my best.

In navigation mode the RMI and PPD-2 give bearing and distance to the RSBN transmitter and deviation from the ground track set on the course needle is shown by the vertical bar on the RMI.

 

In glideslope mode the RSBN-5S adds a electronic glide slope profile to the navigation mode to guide the decent and shows deviation from the profile even if beyond the range of the glideslope transmitter. As well as the vertical bar showing deviation from the ground track, the horizontal bar on the RMI will now show altitude deviation from the descent profile.

3) Landing

 

so you're down safely below the soup, you are 17 km out of Krymsk, everything looks good, but the weather is turning bad into mist and fog (YAAAAY!!!!, not really), you flip the switch to LANDING, you set both SC and RSBN initial heading to 220 degrees (219 actually), then as you approach you start to notice only initial heading moving away from 219 (not hugging the SC needle anymore). You start to panic. Which should I follow??

 

 

So you decide to follow SC needle and regardless of initial heading slowly moving to your left, then all of a sudden, it moves real fast, yes!!

you missed the approach, dummy!!!

 

So *** CORRECT ME *** What is the manner of using LANDING mode when you've used glideslope mode and still facing course 220 and both SC/RSBN needles are hugging eachother intimately? what if you decide to play with initial heading bug? do you follow it as landing course or the SC needle course?? <--- That is the million dollars question.

Again, tricky, I'll do my best.

The course needle is set to the runway heading

The thin RSBN needle will point at the RSBN transmitter which is most likely to side of the runway near the middle, so once I'm on the glide slope/final, I don't follow that.

In landing mode - the RMI horizontal and vertical bars give glide slope/localizer guidance and I fly to them (3° glide slope = 500m AGL per 10km)

 

Lastly, the SC needle. Which is towards (the rectangular hollow or the shorter hollow) and which is away from??

The long end of large double line course needle points along the desired ground track - so towards the RSBN transmitter if flying TO, or away if flying FROM.

 

Again this is how I'm flying and it gets me where I want but it may not be correct - lets hope for some input from real pilots :)

 

Edited July 16, 2016 by Ramsay
Chart had wrong bearings

[Justin Case]

Awesome picture Ramsay, mind if I borrow it sometime?

Edited February 29, 2016 by Justin Case

[Ramsay]

Awesome picture Ramsay, mind if I borrow it sometime?

 

Edit: Found I had the wrong radials i.e. 276° TO Smoleskaya NDB and needed to update the diagrams. Tested in 1.5.4.

 

Use away. Here's the Maykop-Khanskaya Departure

 

and Smolenskaya Holding Pattern charts I did for the same navigation exercise.

Edited July 16, 2016 by Ramsay
Found the radials were 4° out

[Justin Case]

I've been meaning to create similar charts my self but couldn't be bothered earlier since the spark for IFR in my community has been faint, until recently when a few guys seem to be enjoying it.

 

Thanks!

[gospadin]

are those charts from "real life" approach/departure procedures documented somewhere?

[Ramsay]

are those charts from "real life" approach/departure procedures documented somewhere?

The charts are made up,

 

• 
  
• the curving arc of "Krymsk Arrival" is based off the real ILS DME Rwy 13R chart for Tiblisi
  
• "Maykop Departure" is done in the style of an official AIP departure chart to make it believable/educational
  
• "Smolenskaya Hold" is from a real AIP chart that uses the NDB, as are the other NDB info boxes.
  

Edited February 29, 2016 by Ramsay
typo

[WildBillKelsoe]

nice work ramsay

 

 

Sent from my iPhone using Tapatalk

[WildBillKelsoe]

but if PRMG truck (a separate truck) is to the side of runway, should the localiser be skewed and followed skewed (not pure ILS??)

[Ramsay]

but if PRMG truck (a separate truck) is to the side of runway, should the localiser be skewed and followed skewed (not pure ILS??)

I don't know how the RSBN-5 system works ...

 

<snip bad guesswork/wrong info>

 

Here is a product description of the RSBN-4NM system

 

and a google translate of https://de.wikipedia.org/wiki/RSBN which describes the RSBN system

 

Components: RSBN VOR, Rangefinders / PRMG approach and landing system

 

In rich it consists of VOR, distance meter (bottom-side and air-vehicle Retranslatoren ) RSBN and associated approach and teilautomatisieten landing system PRMG ( Russian приводная радиомоячная группа, priwodnaja radiomojatschnaja gruppa), which is essentially how the ILS functions, but is much more accurate. By RSBN system the position of the aircraft according to the direction and distance with respect to the VOR is determined, while the PRMG system the landing from 80 km before touchdown and landing itself automatically to the so-called decision height of about 30 m takes over ground. From this point, the landing is done manually by the pilot.

 

Radio Technical principle of direction determination

 

Similar to a VOR beacon with rotating radial radiation , it consists of a rotating signal and a non-directional signal. It sends a 100 / min rotating double-lobe-shaped signal and 2 pulse sequences undirected reference signals (every 10 degrees per double lobe circulation 36 bursts and all 10.28 degrees 35 pulse trains). In northern reference point both pulses coincide. The distance between the 36s and 35s pulses increases with continuing rotation of the double lobe signal. The device on the aircraft measures the minimum betw. Two lobe signals as sweep time (The minimum is determined with higher accuracy than the maximum). By counting the 36s pulses, ie every 10 degrees, it is determined what part of the Azimut is a fine counter measures the time between. Double lobe minimum and last 36er pulse (at the north and south, ie 0 degrees and 180 degrees, is new adjusted). the azimuth angle is theoretically determined with an accuracy of 0.02 degrees from two counter samples. The accuracy results from the frequency used, the fine counter. In practice, the display accuracy is limited by the processing in the subsequent electronics and the display device. It is here, of 0.2 degrees. Thus, the RSBN system is more accurate than VOR / DME ( VOR ).

 

Operating principle of the distance measurement

 

Essentially as DME distance measurement works (interrogating beam 30 Hz, 300 Hz impulse response), but with an additional query direction information. A Morse code of the station can be switched.

 

Principle of operation is a secondary radar.

 

A emitted from the ground pulse is actively answered by the aircraft, the duration is measured at the bottom and it determines the distance. Both the ground -as well as the air-vehicle stations are en interrogator and a responder, so that both stations are each independently the distance can be determined for each other.

 

 

Associated devices and displays in the cockpit

 

The respective RSBN station with a channel selector (up to channel 88, some remarks to Channel 40, newer systems to channel 176) dialed (116 MHz to 117.95 MHz / 770-1000 MHz).

 

The following selection of typical devices and display modes allow extensive position, distance and direction determinations:

 

The direction finding direction and deviation are generally on a switched on RSBN HSI compass ( horizontal situation indicator displayed) and VOR indicator and some additional equipment. There are RSBN specific displaydevices and their modes of operation:

• 
  
• "Azimuth to" and "azimuth from" radial to / from the station RSBN
  "Left orbit" distance counter-clockwise to the right of Station (station is left of the plane)
  "Right orbit" distance clockwise towards Station (Station is the right of the airplane)
  
• "SRP" flying over a point within the range of RSBN station with the definition of "target angle" (angle to the target) and the "target distance" (distance to destination). Given the "ZPU" "virtual course angle is" determined by the station. (If target angle = ZPU, then the plane flies away from the RSBN station, he is = ZPU + or - 180 degrees, it flies to RSBN station)
  
• "KPPM" device for vertical and horizontal guidance for RSBN, as well as VOR and ILS
  
• "PPDA" true bearing and distance relative to RSBN station. If the bearing = azimuth and distance = orbit, then the goal is reached.
  

 

and a description of RSBN by Krzysztof Burbo who was commander of the instrumented landing system PRMG-5 in 8 Regiment Fighter - Bomber in Miroslawiec

Author, Krzysztof Burbo is a lecturer at the Centre for Training in radio-Jelenia Gora on the Cycle Insurance Flight. Before that for seven years he was commander of the instrumented landing system PRMG-5 in 8 Regiment Fighter - Bomber in Miroslawiec.

 

Radio navigation system close RSBN

Radio navigation system close RSBN-4N is a non-directional radio navigation device for measuring the azimuth and distance of the aircraft from the point of developing the system. RSBN-4N in cooperation with the apparatus board

 

RSBN-5S (or later) provides:

 

• 
  
• Continuous transmission of the pilot on board the aircraft the place of its location in polar coordinates (azimuth, distance);
  
• Derivation of the aircraft in any designated point lying within the system;
  
• Determine the moment of arrival of the aircraft to a designated point and the time to fly over point;
  
• Correction autonomous meter distance traveled;
  
• Flight from using the autopilot;
  
• Driving, using a circular observation indicators (WOO) system, terrestrial observation air situation within RSBN-4N, or determining the position of aircraft and their classification;
  
• Administration on aircraft reconnaissance signal.
  

The position of the aircraft using the system RSBN defined in the polar coordinate system, using:

 

• 
  
• measuring the distance of the aircraft from the point of system settings,
  
• determine the azimuth line, passing through the point system settings and aircraft, in relation to the geographical meridian
  

Measuring distances on board an aircraft is carried out by means of a pulse telemeters working on a transponder. The distance of the aircraft from the point of development of the system is determined by the measurement (on board) signal transition time asking for the device ground and the response signal from the device ground on board the aircraft. The time measured with sufficient accuracy is processed in the distance of the aircraft from the system.

 

On board the aircraft azimuth is determined by measuring the time elapsed since the initial - determined by a signal "convergence northern" common to all vessels within range of the system, until receipt by the aircraft azimuth signal. The antenna supplied with the transmitting device emits a continuous vibration dwulistkową directivity. Turning at a constant (stabilized) speed opromieniowuje turn all aircraft within range of the system.

In the rotation axis azimuth of the antenna are mounted discs senders electromagnetic pulse generating reference signals provided for determining the angular position of the minimum azimuth antenna characteristics at any given time with respect to the north of the minimum sheet.

ROTAX electromagnetic produce two series of signals model, which convergence occurs when the minimum radiation pattern of the antenna azimuth coincides with the direction of the north. Then the signal is emitted so. "Convergence North" - common to all aircraft (within the system), which is the initial point of reference against which determines the azimuths of individual vessels.

Second signal called. "Azimuth" is received on board when the minimum characteristics of the antenna is aligned with the direction on the aircraft. The time interval between receiving two signals on the board: "The convergence of the north" and "azimuth" is proportional to the azimuth of the aircraft.

 

It should also be noted that the on-board device RSBN can work on two areas: the navigation and landing.

On the scope of the navigation aircraft position information is obtained by beacon azymutalno - spacer (the principle of operation described above) which protects the semi-conducting aircraft on the prescribed track and continuous measurement of the azimuth and distance.

 

On the field of landing (in cooperation with a ground system landing PRMG ) is programmed aircraft landing and automatically maintain the glide path and the axis of the course during the approach to landing at the same time indicating the distance to the point of touchdown. In both areas of work can be turned on an additional type of work "piercing the clouds." In all areas of the system allows you to monitor the movement of aircraft on the screen ground station.

 

The program board device can enter the coordinates of the four beacons ground, three waypoints (PAC - change points of the course) and data to land four airports.

The system generates the bearing and distance to the PAC or to one of radiolatarń and allows maneuver incident to land on one of four preset airports. Until the inlet plane in the area of ​​the course and glide slope flight is performed semi-automatically, in areas - automatically. Exit the airport landing carried out at the sub-range "Return". The transition to the scope of "Landing" is done automatically or by using a switch. Automation allows you to perform repeated approaches.

 

Beacon RSBN-4N, Photo: Krzysztof Burbo

In the photo: beacon RSBN-4N with a distinctive cover the antenna rotation.

Photo: Krzysztof Burbo.

 

The ground equipment RSBN includes the following elements:

 

• 
  
• Beacon system from the point of control wynośnym;
  
• Desktop dispatcher;
  
• One or more indicators wynośnych observation circular;
  
• System Antennas-fiderowy;
  
• Generator set;
  
• Ventilation and cooling;
  
• The lighting system.
  

The operating range beacon system is dependent on the altitude of aircraft and amounts:

 

• 
  
• 500 km - the altitude of the aircraft 35 000 m;
  
• 380 km - the altitude of the aircraft 12 000 m;
  
• 250 km - at the height of the plane 5 000 m;
  
• 50 km - at the height of the plane of 250 m.
  

The number of aircraft that can use the data channel azimuth is unlimited, and the number of aircraft using the rangefinder channel is not more than 100.

The diameter of the zone of unstable indications (cone dead) over the beacon of the system is approximately 3 km at an altitude of 3000 m.

The accuracy of the azimuth of the apparatus board RSBN-6S is 0.25 ° accuracy of determining the distance of 200 m.

The screens ratios follow the circular coordinates of the aircraft is determined by the accuracy of the deployment of markers:

 

• 
  
• The azimuth: 1 °
  
• At a distance of 3km, with a range of 100 km and 6 km at an amount equal to 400 km.
  

The frequency range of broadcasting equipment beacon system is:

 

• 
  
• The channel azimuth 873.6 to 903.7 MHz and 905.1 to 935.2 MHz;
  
• channel rangefinder 939.6 to 1000.5 MHz.
  

Frequency channels is 88. Tuning of the transmitter from one frequency to another is manual.

 

Krzysztof Burbo

17-02-2001

 

 

Source http://www.heading.pata.pl/rsbn.htm

 

A little video

 

and a map of the RSBN-4 antenna layout

 

<snip bad guesswork/wrong info>

Edited March 1, 2016 by Ramsay
Remove bad guesswork/info, formating

[Ramsay]

Found a good description of the PRGM-5 landing system - which is what your question is really about.

 

TL;DR - Yes, the PRGM system will have error but with a centreline accuracy of ±10.5 m at 15m altitude, it is sufficient to reach the visual/decision point.

Google translation of http://www.heading.pata.pl/prmg5.htm

The instrument approach PRMG-5

 

Russian military system approaches PRMG-5 was for many years the standard for the air forces of the Warsaw Pact countries. As befits a system approach, the system gives the direction of the landing glide slope angle and distance inclined to the runway threshold. As it is designed for military aircraft, is distinguished by several features unprecedented in civil devices.

 

The operating principle PRMG-5 is similar to the system ILS . It is based on production in the space of two flat and mutually perpendicular beams of radio waves: a horizontal beam and a vertical glide path beam direction of approach.

The visible part of the system consists of three beacons: beacons direction (called the beacon of the course - DKRM), beacon glide path (GRM) and radiodalmierza (RD). A typical installation of transportable system includes a dual set of radio beacons, securing the main and backup direction of approach.

 

Beacon beam direction is equal to the depth of modulation zone, which lies on the axis of symmetry axis of the DS and passes through the center of the antenna, and sets the direction of landing. Radiation is so arranged in the space that viewed along the direction of approach to the landing on the right side prevails RF signal modulated signal with a frequency of 1300 Hz, and the left - a frequency of 2100 Hz. Both signals are transmitted alternately with a switching frequency of 12.5 Hz.

 

Beacon direction KRM-5 operates in the frequency range from 905.1 to 932.4 MHz. The effective range of the signals is 45 km at an altitude of 1000 m (transmission power 8 ). In the horizontal plane the sector is limited to +/- 15 ° from the direction of approach. In a vertical plane from 0.85 ° to 7 °.

Radiodalmierza antennas are located together with the beacon - varieties than in ILS. Operating on the principle radiodalmierz transponder operates in the frequency range from 939.6 to 966.9 MHz. Pulse radiodalmierz (incompatible with DME ) is similar to the standoff channel system RSBN and has a precision of +/- 250 m.

 

Beacon glide path (GRM) works in the same beacon direction. Antenna paths are located on the side of the runway, 120 to 180 m from the center and 200 - 450 m from the threshold.

The frequency range is from 939.6 of 966.9 MHz. The range of signal path is 18 km away in the +/- 8 ° to the direction of approach.

 

For reading the PRMG on the plane is the cross-hairs, similar to the CDI (cross deviation indicator).

 

Onboard equipment type Receiving RSBN-5s, RSBN-6s-7s RSBN, A312 / 10 A323 are able to guide the aircraft to a height of 15 m above the plane of the runway with a horizontal accuracy of about 10.5 m from the center line.

 

So PRMG-5 has a pretty decent performance for a device carriage. However, it is very common system; found in principle only in the countries of the former Warsaw Pact (plus perhaps India and Vietnam). In recent times it was so secret that when the Russian Office of the Commercial Counsellor asked about the specifications, was wykierowany the door to the accompaniment of ugrzecznionych grunts. For the uninformed I will add that the BRH in the socialist countries was simply the official arms dealer.

 

It must be assumed that the system approach PRMG will be withdrawn from the weapons of our air force even before the complete changeover on planes western production. This does not mean a quick end; is impeded by lack of money and common treatment for the purchase of any military device as a political decision. And politicians, as can be seen with the naked (ie. The indigent :) eye, preferring off steam in the topics "extremely momentous" though not threatening any real responsibility. So far, the biggest modification of our combat aircraft was to install a transponder IFF compatible with NATO equipment and civil.

Hope this answers part of your question (sorry about the previous bad info). Edited March 1, 2016 by Ramsay
Add TL;DR as there is a wall of text

[Skulleader]

Hello guys,

 

Ramsay your explanation is really awesome but sometime my English is not perfect and I would like to know if it's possible to have your track file ?

A track file is really better that video because we are really inside the cockpit, Ramsay please do you know if it's possible to have this track file ?

Once again a great thanks, Skull

 

 

[uboats]

nice tutorial

 

 

Sent from my iPhone using Tapatalk

[Ramsay]

Ramsay your explanation is really awesome but sometime my English is not perfect and I would like to know if it's possible to have your track file ?

Sure, I wanted to test my optimum climbs and it seemed silly to fly an ILS approach with good visibility, it's an excellent example of how not to fly it

 

• 
  
• the mission text is for a different flight with different weather
  
• I planned my flight way too high at 6000 m
  
• so was too close/high when I switched to glideslope/penetration mode after Smolenskaya NDB
  
• turned late for the 20 km arc
  
• turned too early for final
  
• my height was all over the place
  

You get the idea - hope there's something good in it for you, even if it's only a lol.

[Justin Case]

I can make a video on Friday, unless someone else steps in before me.

[Skulleader]

Sure, I wanted to test my optimum climbs and it seemed silly to fly an ILS approach with good visibility, it's an excellent example of how not to fly it

 

Super Ramsay,

A great thanks it's really awesome from your part, tonight I test this method.

Thanks again, Skull.

[Ramsay]

A great thanks it's really awesome from your part, tonight I test this method.

If I fly this altitude profile again, I think I'll

 

• 
  
• enter the holding pattern at Smolenskaya NDB at 6000m
  
• Set the RSBN/PRGM channels to Krymsk on 28/26
  
• Switch to Glideslope/penetration mode while in the holding pattern
  
• Descend to glideslope altitude at the NDB using the RMI horizontal bar for guidance. Might be about 3,000m ( (DME 65 -10km) x 50m/km = 2,750m) if I've got my maths right.
  
• Contact Krymsk for Runway, QFE, etc
  
• Leave Holding pattern on 283° and follow the ground track/descent profile to Krymsk Arrival RSBN KW D 24.0 R 104°
  

We used to fly at about 2,500m for bad weather penetration/night exercises, and to the NDB Flight Levels for course/pattern/landing with crosswind exercises in visual meteorological conditions.

 

Even if my next flight is text book, I'll leave the previous track here because a bad flight is always more educational than one that goes smoothly. :)

 

Edit:

For info: The optimum climb profile I'm testing from the L-39ZA Flight Manual is

 

• 
  
• Maximum Power - 106% (20 min max), then 103% Max sustained
  
• 400km/h IAS until 500km/h TAS (thin airspeed needle)
  
• then maintain 500km/h TAS (allowing IAS to fall)
  
• Air speed is controlled by pitch/ascent rate
  

Until desired cruise altitude is reached.

Edited March 7, 2016 by Ramsay
Add Optimum Climb info, grammar

[Ramsay]

Vyrtuoz has released a set of textures for Tacview that make checking NDB IFR flights very easy.

 

 

I found a major error in the charts I shared previously, so have corrected the charts in posts #2 and #4

 

For that region of the Caucuses map

TRUE = F10 map

MAGNETIC = F10 map - 6°

ISO (terrain) Grid = F10 map + 4°

 

Tested in 1.5.4

 

 

Main Tacview VFR ground textures thread

Edited July 16, 2016 by Ramsay
Correct bad info on F10 map bearings

[WildBillKelsoe]

Awesome man, just awesome!

We can't thank you enough!

 

Sent from my SM-T231 using Tapatalk