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About JRBarrett

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  • Birthday 11/09/1955

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  • Location Elmira, NY
  1. "Engine Rise Temp" switch

    I believe that normally, it would be set to "rise". This system monitors the oil temperature of the generator drive units on each engine. The "generators" on a 737 are actually "alternators", which produce 3-phase AC voltage at approximately 118 volts. The problem with an alternator is that the frequency of the AC voltage it produces will vary with the speed that the engine is turning, but the systems on the aircraft depend on the frequency of the AC being precisely 400 Hz. The generator drive unit sits between the engine accessory gearbox, and the generator. It works somewhat like an automatic transmission on an automobile, and will turn the generator at a constant speed, no matter what speed the engine is rotating. The drive unit has its own dedicated oil supply, oil pump and oil cooler. When the switch is set to "IN", the lower scale of the gauge is measuring the temperature of the oil that is entering the drive unit, after passing through the oil cooler. In "RISE" position, the associated gauge is showing the relative increase (rise) in the oil temperature after it has passed through the drive. (Read on the upper scale). If the temperature rise of the oil, after passing through the drive unit, exceeds 20 degrees C, it could indicate the the generator load is too high. If the temperature gauge reads in the yellow zone with the switch in the "IN" position, it would likely mean there is a problem in the oil cooler. Questo messaggio c'est envoyé von meinem iPhone using Tapatalk
  2. Does a new hot fix depend on the preceding one?

    Thank you. Questo messaggio c'est envoyé von meinem iPhone using Tapatalk
  3. Was curious if the hot fixes for the 733 are cumulative, or if they depend on the preceding hot fix? I am currently running 1.03 - may I update directly to 1.05, or should I install 1.04 first? Thanks! Jim Barrett Sent from my iPad using Tapatalk
  4. switch INOP in cold and dark

    I can't say for sure regarding the 733, but in most aircraft, the auto throttle switch is electrically latched to the "on" (or "arm") position, and cannot be engaged when the aircraft is unpowered. This would appear to be normal behavior. Sent from my iPad using Tapatalk
  5. [1.0.4] Weird fuel temperature displayed

    It can be difficult to find an exact value for the cooling rate, since there are so many variables. Initial temperature of the fuel, quantity in the tank, size and shape of the tank etc. The problem of Jet-A cooling to the point where freezing potentially might become an issue mainly affects aircraft on very long transoceanic flights which spend many hours in cruise. The opposite effect happens too - once thoroughly chilled, the fuel remaining in the tanks can take quite some time to warm back up after landing. On very humid days, I've seen ice form on the underside of the wings of aircraft that have just landed from a 5-hour transcontinental flight - even though the air temperature might be over +20C!
  6. [1.0.4] Weird fuel temperature displayed

    Aviation jet fuel takes quite a long time to cool from whatever temperature it had when it was placed into the aircraft tanks. Depending on the aircraft's speed, fuel that started out at +20C on the ground, could take over 2 hours of exposure to -50C temps aloft before its temperature would drop significantly below 0C. Even then, the fuel will only drop to the TAT (True Air Temperature) "felt" by the airframe structure, which is often 10 to 20 degrees C warmer than the SAT (Static) OAT. The difference between SAT and TAT depends on the aircraft's speed. Of course, the rate at which the fuel cools depends on many factors. Fuel loaded in the tanks in Miami in July at +40 C, will take much longer to chill down in cruise, than fuel loaded in Boston in January, which might have already been cold-soaked to -5C in the fuel truck before even going into the aircraft. The size of the tanks plays a roll too. Fuel stored in thin wings will cool faster than fuel in thick wings (more capacity). And, fuel in wing tanks cools faster than center tank fuel, for similar reasons. In any case, seeing fuel significantly warmer than ambient OAT is perfectly normal until the aircraft has been at sustained cold temperatures at the flight levels for quite a long time. I have seen many add-on aircraft (mainly in FSX) that get this completely wrong - where the fuel "instantly" assumes the outside air temperature in a climb - which is not what actually happens in a real aircraft. Questo messaggio envoyé von meinem iPhone utilizando Tapatalk
  7. Be sure that the degrees portion of the longitude contains 3 digits. In other words, if your longitude is 75 degrees, 14.5 minutes west, you would enter in as W07514.5 or if the longitude was 5 degrees, 14.5 minutes, you would enter it as W00514.5 Likewise, the latitude degrees entry needs a leading zero if the current latitude is less than 10 degrees. Not sure if this is the cause of your problem, but it is one common user error that would prevent the IRS from accepting the PPOS. Although it is possible to enter your present position directly into the IRS control unit in the overhead panel, the more typical procedure would be to key it in using the FMS CDU. Sent from my iPhone using Tapatalk
  8. The pilot's VOR course selector on the flight guidance panel shows "0" when a course of due north is selected, while the copilot's selector displays "360". I have seen both ways of displaying a north track in actual aircraft, and either is correct - but usually both selectors are the same. It's no real problem, and perhaps there is a reason why it is configured this way due to the way XP works internally.
  9. Bug report list part 4

    Yes, but don't confuse the function of the two switches. The 5-position switch on the left side marked OFF, TA, TA/RA, ABV, BLW controls the TCAS, which works WITH the transponder, but is not the transponder itself. The transponder is controlled by the 3-position switch on the right side marked STBY, AUTO, ON. When the transponder switch is in AUTO mode, it will not transmit on the ground. As long as the weight-on-wheels sensors on the landing gear detect that the aircraft is on the ground, the transponder remains in Standby. It will start transmitting the squawk code and aircraft altitude as soon as the aircraft becomes airborne. In ON mode, the transponder is active no matter what the aircraft's air/ground status is. In STBY mode, the transponder remains off, even if airborne. A summary of switch positions would be: NON ASDE-X airport: Leave the TCAS switch at TA/RA, and the transponder switch at AUTO. (This is the IXEG default state). In this scenario, the transponder comes ON at takeoff, and goes into STBY on landing. ASDE-X airport. Set the TCAS switch OFF, and the transponder switch ON, once pushback commences. When cleared for takeoff, switch the TCAS switch to TA/RA. Once airborne, you can switch the transponder from ON back to AUTO. If landing at a NON-ASDE-X airport, just leave the switches in the default positions: TCAS at TA/RA, and transponder at AUTO. If landing at an ASDE-X airport, switch the transponder from AUTO to ON at some point before touchdown. After landing, and after exiting the runway, leave the transponder ON, but turn the TCAS to off. Once parked at the gate and shutdown, go back to default positions: transponder to AUTO and TCAS back to TA/RA. Of course, X-Plane airports don't actually have ASDE-X, so for the majority of users, just leave the TCAS and transponder switches at their default positions. The above techniques are really only for those who want to practice real-world procedures with 100% accuracy. If you want to know if a particular airport has ASDE-X, you can download the r/w airport taxi diagram from a place like SkyVector. If ASDE-X is in use, there will be a note on the chart instructing pilots to turn transponders ON while taxiing.
  10. Track distortion problem

    And a track distortion can happen on a basic RNAV Departure too ? ++ [emoji4] The results with a true RNP approach are unpredictable, since the FMS is not capable of dealing with curved leg segments - but other strange graphics artifacts on normal RNAV approaches or departures may indeed be bugs which have to be addressed by the developers.
  11. Bug report list part 4

    Some additional background on the TA/RA switch. (I am an avionics tech for a corporate jet operator). As long as the transponder is in "standby" mode on the ground, it is OK to leave the TCAS set to TA/RA. The TCAS processor is a separate unit from the ATC transponder. It has two directional receiving antennas - one on top of the fuselage, and one below. These antennas receive signals from the transponders of other other aircraft in flight, and the TCAS calculates the bearing, distance and relative altitude of airborne targets. The TCAS has no transmitting ability on its own. In order to send interrogations to other aircraft (known as "squitter"), the TCAS uses the transmitter portion of the aircraft's transponder as its link to the outside world. As long as the transponder is selected to standby (either manually, or automatically via weight-on-wheels sensors), the TCAS cannot transmit. In years past, it was always standard practice to place an aircraft's transponder in STBY mode as soon as exiting the runway after landing, and to not turn it on until entering the runway for takeoff. Now, however, many large airports with heavy traffic volumes are equipped with surface detection radar known as ASDE-X, which permits ground controllers to see the exact positions of taxiing aircraft, even at night or in conditions of poor visibility. At such airports, all aircraft moving on taxiways are required to turn their transponders "on", so ground controllers can see them on ASDE-X. In this situation, the pilot should turn the TCAS to STBY or OFF, to prevent it from sending squitter interrogations through the transponder, which could cause false TCAS alerts in other aircraft which are in the process of taking off or approaching for landing. Many aircraft are equipped with ATC control panels which combine both TCAS and transponder control in a single rotary knob - with transponder modes coming first, followed by TCAS modes. The control panel emulated in the IXEG 737 is one in which the transponder and TCAS mode selectors are separate.
  12. cheesy route drawing at KPSP RNAV Y 13R

    Probably depends on the operator's route structure. If they serve a lot of airports with RNP approaches, it would be worth the cost to upgrade. More and more RNP approaches are coming online every month worldwide.
  13. cheesy route drawing at KPSP RNAV Y 13R

    Hand flying is always approved! (Especially at PSP, which often has very clear skies). There may well be some 733s which have been updated for RNP approach capability - especially those which have been converted for use as business jets. Many 737-600, 700, 800 and 900 NG aircraft are RNP capable. I believe all of those manufactured in the last 5 or 6 years are - but the upgrade path to add RNP to the older Classics are probably too expensive for most operators.
  14. Track distortion problem

    This is similar to the issue I responded to in another topic entitled "Cheesy route drawing at KPSP". Like the RNAV approaches at Palm Springs, the RNAV02 approach at Toncontin is an RNP RNAV approach which uses curved leg segments. Typically, the FMS in a r/w 737-300 would NOT be capable of flying RNP. At the time that the FMS in the Classic 737 was designed, curved RF legs did not exist. Not all RNAV approaches are RNP, but those which are, cannot be flown by a "stock" 733. That's not to say that other types of distorted track displays in the IXEG 737 might not be caused by programming bugs, but in this instance, it is a limitation of the real aircraft, which might very well display similar track distortion if an RNP approach was attempted. Sent from my iPhone using Tapatalk
  15. cheesy route drawing at KPSP RNAV Y 13R

    The RNP approaches at PSP require an FMS capable of plotting and following curved RF (radius-to-fix) legs. The FMS in the 737-300 was designed and certified long before RNP RF procedures were implemented. Unless it had extensive avionics upgrades, a real 737-300 would not legally be able to fly any of the RNP approach procedures at PSP, and would likely show similar distortion on the NAV display if it did try to follow the approach course. The only instrument approach legally available to a typical 737-300 at Palm Springs would be the VOR/GPS-B Sent from my iPhone using Tapatalk