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I once had the opportunity to look down at an aircraft doing a transonic fly-by... while standing on the ground. :music_whistling:

The antennas which serve one runway have a back lobe radiating in the opposite direction. There are antenna designs out there which suppress that back lobe almost entirely, but they are by and large the exception. You are thinking published procedures, but I'm talking antenna design and behaviour/performance.

All the commonly found localizers have a back course lobe, extending in the opposite direction from the main lobe. In the US, this lobe is even used to fly back course approaches. As for hearing the ident on the ramps, you are pretty darn close to the antenna so I wouldn't be surprised to hear the ident even when outside of the 70 degree coverage sector. I'll check as soon as I remember.

35 degrees either side of the final approach course, so not all that narrow. Lots of the airport will be covered. Outside of that you tend to get static rather than an ident. You'll also tend to hear it when on the approach to the opposite runway, as most localizer facilites have a backcourse beam, with varying strength depending on the type of localizer.

Towards the aft end of the left side panel you have a panel with volume knobs for the various radios, including ILS and TACAN ident. Push/pull for on/off.

But the WGS coordinates of the NDBs are published, so punch those in as a steerpoint and use steerpoint mode on the HSI as a faux ADF. Service volumes were fixed in the final release, so published procedures are now possible.

Heights are a rather more complex subject than most assume. UTM and MGRS reside in the WGS84 (World Geodetic System) reference system. WGS84 defines the coordinates for positions across the surface of the earth. It also defines the surface of the earth as an ellipsoid, the WGS84 ellipsoid. This ellipsoid is a rough approximation of the actual surface of the earth. Three-dimensional coordinates under WGS84 include a height above this ellipsoid - ellipsoid height. (This is a height and not an altitude, so no need for reference pressures (QNH/QFE/QNE).) This height is not the same as the height above mean sea level. There's another earth model defined, the geoid, which describes the shape the earth would have if it was completely covered with water - a theoretical sea level surface, covering land and oceans alike. This is a rather uneven shape. Variations in the distribution of the mass of the earth will cause local variations in gravity. If you e g have a large ore body in the crust of the earth, or a mountain, the mass concentration will cause a local increase in gravity which pulls water in, thus raising the surface of the geoid. The neat thing about the geoid is that local gravity is always perpendicular to the geoid surface. For every point on the planet, there is a geoid undulation, which is the height of the geoid (or the theoretical sea level surface at that point) above the reference ellipsoid. To convert the height above the reference ellipsoid, e g as reported by your GPS operating in WGS84, to a height MSL you need to subtract the geoid undulation. What we enter should be the ellipsoid height - the height which a GPS would report. The aircraft would then need a geoid model to convert this to a height MSL, if this is desired for some reason. As the aircraft lives in WGS84 already, it really only needs the ellipsoid height for the systems to do their job. Cheers, Fred

If there is any doubt whatsoever, JTAC is supposed to give the grid zone. They don't in DCS, which is a bug. 37T/38T is the grid zone BTW. The easting is the first half of the numbers in the coordinate. The complete MGRS coord would be eg 37TAJ482340.

Either your procedure is... let us call it interesting, or there is a misunderstanding. I'll assume the latter, so let us try to clear it up. What speed do you have when crossing the runway threshold in your light aircraft example? 150 knots or 119 knots? Cheers, Fred

If flying an airliner... :) (Or, granted, on the ILS)

Nor would MN568030 (never spaces in a MGRS coordinate, if you want to be strict about the standard - we're not, where I'm using them in real life) be read out as MN56830, which is what DCS:A-10C does currently. ;) Unfortunately, it also reads out MN056830 as MN56830, so you've only got a 50/50 chance of guessing it right. It is a bug.

The issue is the runway you are eating up as you are decelerating from 150 knots to 119 knots. The best way to increase the runway required to come to a stop is to nudge the speed over the threshold up a bit. Chews up runway meters like there is no tomorrow... or at least no far end of the runway. "But I have plenty of runway"? Yes. But if you had the right speed over the threshold, you'd have more of a margin for low surface friction, brake failures etc. You'd come to a stop sooner, enabling an earlier turnoff and more efficient use of the runway. You'd be at a lower speed as you descend into bird-strike territory. You'd be able to coast to a stop and save break and tyre wear. Gusting/windy conditions is about the only time carrying excess speed can be tolerated - if there is runway to spare. While I'm writing I'd like to say thanks to those pointing out that you should always mind your calculated speeds as well as the indexer. That was me sim-simplifying real-world procedures. Cheers, Fred

In short, no. Nor do you generally need to. The AoA indexer takes away the need for a speed book.

Unless the system was changed from the A-10A in such a way that functionality was lost and instruments duplicated instead (i e not very likely), the ADI bars should be what they were in the betas - command steering bars and not ILS CDI repeaters. I'd strongly suggest using the GP needle on the left of the ADI and the HSI CDI localizer needle, or chances are you will have to relearn once the proper functionality is re-implemented. Command steering bars are effectively an autopilot system, using the pilot to activate the controls. Needle above center tells you you need to pitch up to center the glide path. As you pitch up, it centers - even if you are still below the GP. No official word on this though. Cheers, Fred

The elevator artificial feel device is also the normal mode elevator trim. It changes the zero stick force elevator position when you are trimming. When hydraulics are lost, electro-mechanical actuators drive the trim tabs to provide trim. I'm not sure (as in 'have it from an authoritative source') what happens with the artifical feel in case of hydraulics loss. I believe they will still be in the circuit, but be rendered completely insignificant compared to the aerodynamic loads. You'll be overpowering them with trim and then making the final adjustments using muscle power on the stick. Aileron artifical feel and trim operate in the same way in normal mode. In manual reversion, the stick is connected directly to the trim tabs which will then act as servo tabs as described in my post above. All from the A model dash one - a must read if you want to know the A-10 systems. Cheers, Fred

In my experience, the primary indication of a bird strike is usually hearing "holy crap, did we hit it?" over the intercom. Then you look for dents and blood after parking. 200 knots equals 100 meters per second. It takes one second to react. Then you have to move the controls, and the aircraft has to react to your control input significantly enough to change the trajectory. Yes, you can see birds at 100 meters - if you are looking right at them against a good backdrop. Usually, you are not looking right at them as you have other things to worry about, and the backdrop will be ground clutter. Besides, the place where you are most likely to find birds is when down in the weeds. Not the place for abrupt unplanned manoeuvring. While bird strikes can do significant damage, hitting the ground does more damage. Largish bird up high, such as a bird of prey circling in a thermal... allright, you've got a good chance. You're much more likely to be attacked by tens of the things launching from the ground as you approach though. SATBs - Surface to Air Tweety Birds. :) Cheers, Fred

<nitpick mode ON> Transition ALTITUDES are published. When you climb through the TA you transition to QNE. The transition LEVEL is given by ATC and might vary depending on meteorological conditions, as it has to be high enough above the TA to ensure separation between traffic on QNE and QNH. As you descend through the TL you transition to QNH/QFE. <nitpick mode OFF> ;) QFE makes sense when you'll be taking off and landing at the same place, you'll be flying visually, you don't know the exact altitude of your take off location and there won't be ATC to give you altitude separation from other traffic. Not visual? QNH is a better choice, as you'll be able to see your real altitude and compare it with obstacles in your map. Going somewhere else? QNH is far better, as it varies only depending on met conditions, not due to field elevation. You know your departure altitude? You'll be able to set QNH without getting it from ATC. See benefits above. ATC altitude separation? QNH will enable separation between traffic in the area. QFE will cause a problem if the traffic originated from different airports. In my neck of the woods, QFE has been the method of choice for military aviation due to the intended modus operandi. I've also spent most of my glider time on QFE, pretty much for the reasons outlined above, only switching to QNH when getting into controlled airspace. QNH isn't sea level pressure. It is the pressure which gives you the MSL altitude at the threshold when at the threshold altitude. A subtle but important difference. Cheers, Fred

Aha! You know that, don't you? See, that proves it... ;)

Yes. YES! :)

+1 Huge problem for the group I attend regular LAN meets with, as outlined in another thread. Third solution, still bad but better than today: Require net connection only for the server during LAN MP sessions.

Guys, my throttle just bricked on me. Dead. Gone. Not seen in-game. Not seen in control panel game controllers. LEDs on, but nothing home. TARGET crashing when I attempted to run a profile. Shut down to power off to the entire computer. Reboot. Still dead. Unplug. Not there (d'oh!). Replug. Still not there. Feck. Read on here and get ready to ship it to France. Moved all switches and moved throttles to idle cut off. Unplugged again. Went "hmmm". Unplugged the A4 USB mouse in the next USB port and swapped the ports. "Bling" goes the computer. The game controller list shuffled. And... there it is. Problem is, for how long? What happened? Poor quality USB lead? Broken solder point somewhere inside the unit? Can't say I'm comfortable with this until I see an explanation from TM on what they found in the repaired bricked units. I just know it's gonna brick on me the day before departing for a far-away LAN. :/

If you are reluctant to ever call air support in on a coordinate, what about artillery support?

Less than twelve hours later: You can't blame ED for not being responsive! I'll go have a severe attack of hybris now. :lol:

I think it's very useful. If someone has a high rep per post quota, I know it is someone I should listen a bit more closely to when he or she is giving advice or stating things as fact than if someone has a low quota. Of course, friend-repping, brown-nose-repping and lunacy like the thread linked above detract from this usefulness. One quick solution to be done with most of it would be to not count rep given in chit-chat.

This turned into a bit of a paper. Important points italicized. The main focus is pitch control, but lateral (aileron) control is essentially the same, just in a less changing context. First off, Chops is the one who got it right. Think of trim as a helper to relieve the pilot of large and/or constant control forces. On many gliders, the trim is simply a bungee which can be made to pull on the stick with a variable force. Early implementations of trim surfaced during WWI. The planes were built for low speed flying and manoeuvring, which meant you had to push the stick forward to stay level at high speed during cruise. Pilots solved this with a bungee cord attached to the panel which they could hook to the stick. Voila! Instant trim! This, however, has its drawbacks. The elevator position, and hence the stick position, effectively determines the angle of attack the aircraft will seek. Google for "static stability" for more background reading - there's plenty. The stick (and the connected elevator) is an angle of attack selector. A constant angle of attack means that for a constant airspeed, lift will remain constant. Another way to put it is that as lift is (more or less) constant due to the non-changing weight of the aircraft, an aircraft will when stick-fixed maintain a constant airspeed. It will do this through adjusting the rate of climb, either at once or through a series of climbs and descents at decreasing maximum climb/sink rates (google "dynamic stability")*. A constant angle of attack means an aircraft which will seek a constant indicated airspeed. This stick-fixed behaviour is desirable. However, the stick force required for a given elevator deflection varies with airspeed. You need a larger force to keep the stick forward in a constant position at a higher airspeed. With the bungee cord solution, the trim force is constant. Hence the stick position will vary with varying airspeed. Not really what you want for trouble-free hands-off flying. Ingenious minds considered this problem and trim evolved. The trim tab was invented. Rather than pushing the stick forward manually to make the elevator go down, or have a bungee attached to pull the stick forward, someone decided to use the same aerodynamic forces which pulled on the bungee cord to replace the bungee cord. If you have a trim tab at the trailing edge of the control, it will apply a force to the control surface as it is deflected. This force will be proportional to the airspeed - just as the force on the main control surface. As the trim tab is deflected, the position the control surface returns to if left to move freely in the airflow is changed. Remember that the elevator position determines the angle of attack. The trim tab changes the position the elevator will return to if you take your hands off the stick. Trim tab deflection changes the stable hands-off angle of attack of the aircraft. Of course, to make the nose go up (increased angle of attack), the elevator has to go up (stick aft) and the tab has to push the elevator up. This means the trim tab has to deflect down in order to make the elevator go up. This is, as we have seen in this thread, counter-intuitive to some people. To raise the nose through elevator up deflection, the elevator trim tab deflects down. Now, as aircraft got bigger and faster, the control forces increased beyond what humans could achieve through control wires and pushrods. One way of countering this was to introduce servo tabs. These are similar to trim tabs, but automatically move as the control surface moves. As the elevator goes up, the servo tab always goes down in order to assist the pilot to move the control surface against the air flow. There have also been light aircraft where anti-servo tabs, operating in the opposite fashion, were used to increase the control forces and achieve better control harmony. Some aircraft have no direct connection between the controls in the cockpit and the control surface, relying on servo tabs to fly the control surface which then flies the aircraft. This too has drawbacks, so eventually powered controls were introduced. Hydraulic actuators move the control surfaces in accordance with commands from the pilot. All fine and dandy, except for the fact that the amount of control surface deflection needed, desired and allowable changes with aircraft speed. This didn't use to be a problem. The pilot's limited muscle force automatically limited control surface deflection at higher airspeeds, meaning x Newtons of control force created a smaller control surface deflection at high speed than at low speed. The physics work out so that the anticipated aircraft response to a given applied control force is reasonably similar across the speed range, albeit with a much smaller control deflection at the higher airspeed**. The controls are loose at low airspeed, and as speed increases they feel as if they are stuck in a concrete block. The aerodynamic forces on the control surfaces stop the pilot from applying large control deflections which would overstress the aircraft. With powered controls, the pilot could move the stick full aft at any airspeed and the elevator would go full up. At high airspeed, this would mean instant disaster due to violently over-controlling the aircraft. The pilot also lost the feel for the aircraft and airspeed normally given through the feel of the forces required to move the controls. This was solved through artificial control forces, or q feel (as the letter q is normally used to designate dynamic pressure, a fancier name for the part of air pressure felt on the deflected control surfaces due to airspeed) was introduced. Actuators are used to increase the forces required to move the controls proportional to the airspeed, just as they would be increased by air pressure acting on the control surface in a non-powered control path. (Another method, commonly seen in FBW aircraft, is to have a spring loaded control, with constant control force for a given deflection, but to limit the deflection of the control surface for a given control deflection depending on the airspeed.) Obviously, as powered controls negate the forces created by the airspeed on the control surfaces, they also negate the forces created by the trim tabs, rendering them useless for trimming. With powered controls, trim has to be introduced by somehow biasing the control system actuators instead. This is what we have in the A-10. Powered controls, with a trim system to change the control surface deflection at which the control force felt by the pilot is zero. However, pilots still need to be able to fly the aircraft if the hydraulics go out. Thus, the trim tabs are still there but are only used for trimming if the hydraulics are lost. In normal operation, they augment the hydraulics which also means they will be in more or less the right position if a transfer to a non-powered mode has to be done. On the A-10, the elevator tabs will act as trim tabs in manual reversion (lost hydraulics) mode, while the aileron tabs will act as servo tabs. No trim tabs on the rudders, as they should normally never be out of center for normal flight. Lose an engine with unpowered rudders and you can expect to have one tired leg upon landing, and try to find a runway without too much of a crosswind. As with most things (except flutter and navigation), indicated airspeed is what matters. You trim for an indicated airspeed, which the aircraft will then essentially maintain if left to its own devices (hands-off flight). Cheers, Fred *) Some aircraft are dynamically unstable and will climb/descend ever more violently. That's not a nice behaviour at all, and beyond the scope of this discussion. **) What you are really looking for is essentially a constant G load for a given control force, which makes things nice and predictable. You know what happens when you apply a given force to the stick, regardless of airspeed.