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tom_19d

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Posts posted by tom_19d

  1. You'll unfortunately have to take my word for it since I don't film while flying (or doing ground ops), but turbine engines just don't work like that (the latter).

     

    It‘s almost as if you think you are the only person on this forum who has ever started an engine. Regardless, I haven’t been disagreeing with you so much in principal as trying to point out that trying to get ED to change anything on this module that doesn’t violate manual limitations is awful tough. Getting them to do it without incontrovertible evidence is a lost cause. Good luck though (again, not sarcasm, more realism is always better in my book).

  2. If Harriers are able to rearm and refuel then good for them, and they're allowed to.

     

    As one of the (occasional) Harrier drivers, I have used FARPS across several of the missions, although admittingly not all, and have never had a problem taking on fuel and ordnance. Except of course, you can't take much of either (not the fault of the mission/server, just weight limitations coming off a FARP pad).

     

    Besides, and many Harrier pilots will hate me for this, once the F-4 arrives it might replace the Harrier in all the missions.

     

    Despite the fact that I like using the Harrier as a striker and because the VSTOL is a fun novelty, I agree wholeheartedly that the aircraft is a bit of a shoehorn fit to this server, and if the F4 materializes I will fully embrace swapping the Harrier for old Double Ugly.

  3. The first video, ...

     

    Cool video (not sarcasm, I actually really enjoy any of the old training films from the various services) but I have a question when I watch it. They only show instruments on super tight shots, with usually just one whole gauge visible. Also, they demonstrate several abnormal start conditions. Do you really believe they actually induced a hot start and dealt with it so expertly on the first try (because you won't get a second take if you don't) that they captured the needle at exactly 845 and it slammed right back down?

     

    Because personally, if I were going to make such a video where I didn't need to show a wide shot of the whole process, it wasn't live, and modern CGI wasn't an option, I would just have maintenance pull the EGT harness apart at one of the cannon plugs back by the engines. Then they could hook up a test set and induce a voltage to show the readings I need to capture. That seems much safer than potentially burning up a perfectly good engine just for a training film. And once they had that done and the camera was already perfectly framing the EGT gauge, I would probably just capture footage of the other "starting abnormalities" and a "good start" as well. This would be much safer and has the benefit of not putting extra cycles on the engines, and it would be easy to dub over whatever sound was required. Of course I can't prove that was the method used to generate that footage any more than I or any other viewer can prove those were actual shots of an actual EGT gauge in a real T38 in real time. But regardless, as you said, the DCS start violates no limitations set forth in the manual.

     

    Perhaps more importantly, at least on their website, the USAF says the T38 uses a -5 engine. Our DCS F5 uses a -21, so I'm not sure trying to match numbers to a T38 is a valid comparison.

     

    Second point: Until now I hadn't paid much attention to the idle EGT indication, but 200 degrees is unrealistically low, especially with such a relatively warm start. Not only is 200 outside the green arc (normal continuous range) of 325-650 degrees (per the current F-5 NATOPS manual), but it is hundreds of degrees lower than the real life J85 engine idle EGT shown in the first video.

     

    There is a difference in published engine limitations between the state "continuous" and the state "idle." By your logic, since the DCS J85 idles in the mid 50s, that is also incorrect. Should it idle at 80% as denoted by the bottom of the green arc? Because right now in DCS as I begin a smooth spool up for takeoff my EGT and N1 both enter the green arc at almost exactly the same times, which is perfectly logical.

     

    This whole thread seems to lend some credence to the design philosophy of removing numbers entirely from engine instruments and just using colored arcs, since from the pilot's perspective the numbers are basically arbitrary anyway. This world has plenty jet engines that have higher temperature / longer duration EGT starting limits than the J85. There is nothing strange about it, it is just the difference between holding a thermometer 1 foot away from an acetylene blowtorch to holding it 5 feet away. The torch temp stays the same, you are just reading the temp at a different location.

  4. Besides that, I have time in 4 different turbine engine aircraft and can safely say EGT/ITT/TOT should never reach 800 during a normal start. Usually they peak anywhere between 550 and 650.

     

    Why? Different manufacturers have different ITT probe placement relative to the burner can so comparing ITTs across makes or really even different models by the same manufacturer isn't particularly useful. Per 1F-5E-1 there is no reason to abort a start until EGT reaches 845 C, so no limitations are being exceeded. I'm not saying you are wrong that most J85s might start a little cooler, and I too would be very interested to see a startup video, but if you were going to squawk "our" F5 with maintenance, what would you tell them? It is performing within book parameters, so how could you really argue a change is needed even if video from another J85 shows a cooler start? Lots of factors are at play here and as you know, even the two engines on the same aircraft will have different indications during start, but as long as they stay within limitations it isn't a concern.

  5. +1 — If it could also save a small text file with the results and the settings that were employed during the test (or post such data in game so it could be captured in a single screenshot) these results could easily be shared here on the forum — it could eliminate lots of speculation, arguments, and bad information.

  6. Good input, buddy! We'll wait then. Let me know if anything gets fixed in that regard, please :thumbup:

     

    Will do

     

    And it's STILL one of my top 3

     

    Phone booth never disappoints, agree with @Brown Floyd, it was a good rotation last night, numerous red and blue aircraft on the mission all the way through until it timed out. I actually got to see this message on Phone Booth just before New Years. I don’t know how common it is but I don’t see that many complete victories on this server (granted I don’t get to fly as much as I used to) but it is nice to see that there are always at least a few people trying to complete the overall objectives.

    9BB4AEC0-909E-4FA0-A379-CC926074C6E5.thumb.jpeg.230e4ada6da9ebae37375f9bb8fa6730.jpeg

  7. Hi Alpen, regarding strong crosswinds, as you know I have always been in favor of more challenging weather but when it comes to wind the F5 still has this bug. It has been confirmed by ED as affecting both the F5 and the F16. It is supposedly fixed internally for the next beta for the F16 but I have seen no such fix confirmed soon at hand for the F5. If you read that thread you will see, but suffice to say headwind/tailwind changes are currently doing some very weird and unrealistic things to the aircraft. Once this gets squared away, I would say have at it with some gnarly winds, good idea from @Velosocuba.

  8. I experimented a little bit with JDAM PK on the A10C last fall. Running 20 consecutive passes using the most consistent and favorable conditions I could conceive, I found 38's to have a success rate of ~75% achieving one pass / one bomb K-Kills on T72s. Full write up / data / tracks here.

     

    In light of that, my feeling since has been, when a tank positively has to go down in one pass under visual conditions, I'm going for the Paveway.

     

    This was using the latest OB of the time (Oct 2019)...if something has been updated or changed since then, kindly disregard.

  9. have you disabled the use of the RWR for the Mig 19 in the mission Alpen as i dont see it in my cockpit

     

     

    Maybe I am missing something, but which server setting could affect the RWR?

  10. I thought I read that comms were also out. You never stop learning this stuff. Thanks :thumbup:

     

    Right on. Kinda hard to say anyway since we don’t really know exactly the BuNo of our aircraft and exactly what documentation should be supporting it...plus the many documented differences between how our Harrier acts and the NATOPs, but I guess we have to struggle forward best we can. Cheers.

     

    Here is the testing post:

     

    Thanks for pulling that link, good stuff. I exhausted my search-fu looking for that post but I feel slightly better now seeing that it was 168 messages deep into that thread.

  11. But once I have battery on I can turn on all the other cockpit lighting without the engine on, so I'm not sure what to think now.

     

    Is that with the APU running? Cold / Dark jet with ONLY the battery switch to BATT the only internal lighting I get is the EDP. Regardless, instrument lights are AC and the EDP is EMER DC on the actual aircraft, I think that is what the OP was asking.

  12. The aspect you have to consider is that Takeoff Rated Thrust (TRT, MAX power, whatever you want to call it) is defined by more factors than just RPM on one or more of the spools.

     

    Using the A10 as an example, when you select MAX thrust, the aircraft is electrically regulating fuel flow to maintain ITT and compressor discharge pressure within limits. So just as YoYo eluded, your fan (n1) RPM at MAX power is going to vary with atmospheric conditions. Page A2-31 of your TO 1A-10A-1-1S-10 shows the chart for predicted takeoff fan speed (PTFS). In the case of the A10, it can range from 86.5 on a brutally cold day down to 77.5 on a extremely hot day.

     

    As many have said, the A10 is be no means unique. A turbine engine will always have operating limitations that encompass more than just fan or turbine speed to establish max power, and max power really has no relationship at all to a 100% indication on a single gauge.

  13. I ummm... *cough* didn't look at NATOPS... :chair: *ouch-ouch-ouch-stopit!-ouchy-ouch* :surrender:

     

    I just tested loading up the different weapon types and doing 2 bombing runs with each.

     

    BTW my NATOPS Vol. I is Change 2, Aug. 2002, and Vol. II is Change 1, May 1998

     

    Haha, very good, I am just always on the lookout for the latest and greatest with regards to publications,

  14. Hey Doc, I think the terminology here is just tripping you up a bit. DCS seems to handle the coordinates correctly, but it only outputs DMS and DDM (degrees decimal-minutes).

     

    For example, I placed my cursor directly on the top of the “1” on runway 13 at Batumi. Without moving my mouse I recorded the DCS coordinates in the various formats.

     

    DMS

    N 41* 36’ 57.50” E 041* 35’ 26.21”

     

    DDM

    N 41* 36.958” E 041* 35.436”

     

    To check this is correct we can take the seconds from the DMS and divide by 60

     

    57.50 / 60 = .958 and 26.21 / 60 = .437

     

    If we want to generate a DD we need to make the minutes from DDM into a fraction of a degree so we will divide the minutes by 60

     

    36.958 / 60 = .616 and. 35.436 / 60 = .591

     

    So DD

    N 41.616* and E 041.591*

  15. Thanks for doing the testing Capt Orso, nice to have another set of data backing up the issue. Just one question I had, what NATOPs are you using? My TAC-050, Volume II is dated May 98. Chapter 5, External Stores Limitations, is the most definitive source for carriage limitations on the aircraft I can find. It shows the Harrier is limited to only 12 Mk82s using the configuration I explained in post 6 of this thread. I’m not doubting you, just wondering where you found an authorization for 14 bombs because I want to be working from the most current/pertinent data!

  16.  

    attachment.php?attachmentid=223021&stc=1&d=1576491756

     

    ... which makes "... Select same slot again -> " not possible.

     

    This screen makes me think you are not in quite the right place to bypass this nasty bug. For me to get it to work, I actually have to be HOSTING the mission I create through the multiplayer interface.

     

    1. Create your mission as normal in the editor. Your Harrier will be start from ramp (cold start) on the Tarawa as a client aircraft. I have tested this from spots 1 and 2, so not sure about the rest but I get the impression you are doing this for SP practice anyway.

     

    2. Save your mission and exit the mission editor.

     

    3. Select multiplayer on the DCS home screen and host a server yourself (uncheck the public server option unless you want to meet random folks I suppose). Start your mission.

     

    4. When you select your role as the Harrier on the Tarawa, you will probably get the dreaded "your flight is delayed" the first time. However, also notice the flashing pause symbol in the upper right -- press the pause key on your keyboard to start the mission.

     

    5. Press escape, select role, select spectator. Then select your Harrier role and you will drop right into game on board the ship with a cold/dark aircraft.

  17. Hello...Is there something I'm missing? Sorry if it was posted already. I can select and deliver 14 Mk-82 Snake Eyes but when I load 14 Mk-82 AIR, I can either ONLY select stations 2,3,5 and 6 or ONLY stations 1 and 7, but not all of them. Thanks for any help!

     

    Hi Defrabo, there is an awful lot going on here when I started digging into this so bear with me. Disclaimer: I am working from the A1-AV8BB-TAC-050, change 1, dated May 1998. This is the latest thing I can find, but until Razbam lets us know our exact BuNo of the aircraft and the documentation they used to build it, if anyone has data from anything more recent/pertinent that contradicts any of this please let me know.

     

    The short answer is that DCS appears to have something coded differently between how 82Snakeye and 82AIR are loaded.

     

    To start, lets look at a loadout of 14 82 Snakeye. When you go into the STOR page, at the top left you will see 82L - 82H. When you select either of these choices, it will highlight all 14 Snakeyes on the aircraft, allowing you to set parameters and release all of them. (I believe, but of course I can't say definitively, that this is what Capt Orso is doing, as he mentions Snakes but never AIRs in his post; please correct me if I am wrong Capt).

     

    When you load 14 82AIRs and look at the top of the STOR page, you see something different; 82L - 82H - 82L -82H. Selecting the leftmost 82 L and H arms ONLY the outboard pylon weapons. Selecting the rightmost 82 L and H arms ONLY the intermediate and inboard weapons (AKA the 12 AIRs on the ITERs).

     

    I am not going to go so far as to say the way the AIRs work is incorrect, however, because I don't know. The reason for this is the BRU-36's (the standard inboard / intermediate / outboard pylons) are NOT allowed to be used for in flight selection of delivery mode (high drag v low drag), whether using the Mk15/BSU-86 fin (Snakeye) or the BSU-85 ballute (AIR). This is because latching pins used to either hold or release arming wires on the BRU-36 are not mechanically driven open during a release and thus can't be trusted for fin selection. However, the BRU-42 Improved Triple Ejector Rack (ITER) IS authorized for in flight selection.

     

    My understanding is that the information on the STOR page we see as pilots regarding the ordnance loaded on the aircraft is programmed into a physical SMC panel external of the cockpit by ground personnel (obviously prior to flight). So IRL, the two bombs on the outboard pylons would be EITHER high drag or low drag, as set prior to flight. The bombs on the ITERs would be selectable in flight. The question THEN becomes; how would the STOR page treat a collection of inflight selectable (IFS) bombs and fixed HI / LO bombs? To that question, I have no answer, but DCS seems to be doing something different with AIR v Snakeye.

     

    Some other points...

    -Mark 82s are absolutely a valid loading on the outboard pylon (no wingtip station on a Harrier)

     

    -Using a MULT of greater than 2 for bombs is prohibited. Only singles (QTY = 1, MULT = 1), pairs (QTY = 2, MULT =2), ripple singles (QTY > 1, MULT =1) or ripple pairs (QTY > 2, MULT = 2) are authorized for bombs. MULT of 3 or 4 are used for rockets.

     

    -A full load of 14 Mark 82s, either slicks, snakes, or AIR technically isn't an allowable loadout. The book calls for running only 2 bombs on the inboard ITERs (so 1-3-2-2-3-1), not sure if there were concerns of a bomb contacting the strakes / gun pods or what...

     

    Finally; because I had never played with this before, I wasn't too familiar with the LD / HD selections on the Harrier. Can anyone actually get an AIR or Snakeye to deploy in a low drag configuration? Short of trying every fuse option, I couldn't get either to drop low drag, whether off a standard pylon or the ITER.

     

     

    All tests on latest OB build 40647.

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