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Everything posted by renhanxue
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Oh so that's where the HT-KRAN is. I knew or at least assumed that LT-KRAN meant lågtryckskran but was confused because I couldn't find a corresponding högtryckskran. I'll amend the original post and also add the oxygen part that I skipped.
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Smørrebrød is a Danish thing, you philistine! Being mistaken for a Dane is an awful insult. I should probably challenge to a duel or something. Rocket pods at dawn?
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I haven't found any actual checklists in the parts of the flight manual that I have access to, but here's one I made myself, adapted from the SFI (flight manual) for the AJ 37 (we don't have the one for the AJS 37, at least not yet). The AJ(S) 37 had a "readiness cart" (beredskapsaggregat, BRAGG) which could provide electrical power and climate control for extended periods while the aircraft is on the ground at high readiness without the engine running. Assuming you're connected to that: 1. Knob SKEDESVÄLJARE (flight phase) to position BER (beredskap, readiness). 2. Switch HUVUDSTRÖM (main power) to TILL. Most onboard systems now receive power from the ground. You will receive master caution and a bunch of warning lights will come on - the ones that are supposed to light up at this stage are marked with a dot on the light panel. The warning light CK (centralkalkylator, main computer) will go out on its own after about 30 seconds. The light RHM-FEL (radar altimeter error) will be lit if the radar altimeter is turned off. 3. Switch RHM (radarhöjdmätare, radar altimeter) to TILL. The warning light RHM-FEL should go out. 4. If you want to do a systems check: knob SKEDESVÄLJARE to position FK (funktionskontroll, systems check), then do a lot of things which deserve their own checklist. Main power must have been on while the aircraft is connected to BRAGG for at least 10 minutes (longer at lower temperatures) for the electronics to warm up before this step can be done. Once done, turn SKEDESVÄLJARE back to BER. 5. Prepare the nav computer by inputting wind speed from weather forecast (helps the nav computer keep track of your position), waypoints, timestamps, runway heading etc. Programming the nav computer is kinda complex and deserves a few manual pages at the very least. 6. Switch LT-KRAN (low pressure fuel valve) to TILL. Warning light LT-KRAN should go out. 7. Push the throttle past the first stop to the MARKTOMGÅNG (ground idle) position, which opens the high pressure fuel valves (HT-KRAN). A backstop will prevent the throttle from being pushed back below this position accidentally (doing that turns the engine off). 8. Switch START to TILL and hold it there for at least two seconds. The engine will now start and once it's spooled up to ground idle and you have hydraulic pressure, most of the warning lights except HUV O STOL (canopy and ejection seat) and SYRGAS (oxygen) should go out. Once the aircraft is generating power on its own, it will automatically disconnect from BRAGG, drop its connection lines to the ground and close the hatches. 9. Close and lock the canopy. 10. Arm the ejection seat with the safety switch next to your head. The warning light HUV O STOL should go out. 11. Turn on the oxygen supply by moving the cutoff valve away from the FRÅN position. The warning light SYRGAS should go out. No warning lights should be lit at this point. 12. Off you go! Once you're in position at the runway and ready to take off within two minutes, turn SKEDESVÄLJARE to NAV (navigering), which will light up the HUD. I've probably missed things - please correct any mistakes and omissions.
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I'm not actually sure. The flight manual implies that the artificial horizon should be displayed on the actual visible horizon, but it's not really stated explicitly.
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There is a Viggen in this picture.
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I don't disagree. Unfortunately I can't find the SFI section that would settle the matter (there's probably a turn performance chart that shows exactly how much altitude is needed).
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I know I've seen a photo of the SE-DXN cockpit somewhere but I can't find it now. As far as I can remember there were some mods but nothing huge - the emergency instructions text on the flat surface below the HUD was replaced with a translation table between metric altitude and flight levels, and there might have been a civilian GPS unit somewhere too.
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That was me, and I'm pretty sure I'm right. "Halv roll" sounds like it would mean just a 180 degree roll, but that's not what it actually refers to in military Swedish (dunno about civilian acrobatic flying). It really does refer to a split S. See for example these two pages from the J 35F SFI, which show that the maneuver does involve rolling inverted and pulling down. As you can see, in the Draken (which accelerated incredibly quickly in a dive and also had problems with generating enough force on the elevons at high loadings) entering a split S was normally (in peacetime) forbidden at any speed at altitudes below five kilometers. See also this diagram though, which shows a minimum required altitude of about 1500 meters if you're pulling 7 G through the entire maneuver:
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There's an electro-mechanical safety interlock that prevents moving the gear lever to the deployed position at >620 km/h IAS or M 0.65. You can override this, though, by pulling the lever out and past the stop. The SFI doesn't explicitly state Vne with gear out, though (at least not in the parts we have access to).
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I think the pilot probably understated his altitude a bit.
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In the interest of not losing things in translation, a "halv roll" (half roll) is better known in English as a split S.
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Before anyone jumps to conclusions, it's apparently some French guy's model from 2009.
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Firing a rb 05 at the Vidsel test range (Robotförsöksplats Norrland).
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They're very different in terms of the scope of capabilities that were desired from them. The F/A-18 is a result of the US requirements to be able to project power anywhere on Earth from its carriers and fly any type of missions, while the AJ (and later AJS) 37 had a vastly narrower mission scope. The entire aircraft was designed around the Baltic anti-ship role, with additional capabilities added on where it was possible and money sufficed. For example, the combat radius isn't very big, but it's just big enough for flying the kind of missions the Swedish air force needed to fly. It didn't have a true inertial navigation system, but since the computer could be pre-loaded with most of the important landmarks etc that didn't really matter, and it didn't have to wait for half an hour for the gyros to stabilize on a cold start. You could punch in latitude and longitude in any order, because the nav system just assumed you were somewhere in the vicinity of Sweden and figured out which was which that way. It was rather unsuited to CAS missions, but the air force didn't operate in that way in the 70's, so it didn't matter. The thrust reverser mainly adds weight and complexity for little gain over a carrier-style hook if you can expect your infrastructure to be mainly intact, but the SwAF couldn't and didn't, so the reverser was needed. It goes on and on like this - the AJ 37 sacrificed "broad" capabilities to win "narrow" ones that suited its role and intended mission there and then. The AJS 37 upgrade was mainly about adding a few new weapons, which made the aircraft only slightly less specialized. If you want an aircraft for Desert Storm 3: The Game of the Movie: Electric Boogaloo, the AJS 37 is not a good choice. It doesn't loiter, it doesn't drop PGM's, it doesn't offer any form of night vision and can't even do a gun run unless you bring pods. On the other hand, if you want to form up 50 aircraft radio silent over Småland and set out at five meters over the sea completely without fighter cover in order to drown the 336th Guards Naval Infantry Brigade out of Baltiysk in a storm of ASM's somewhere east of Gotland, you've got exactly the right aircraft.
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Not a sticky, but here you go: http://forums.eagle.ru/showthread.php?p=2804126#post2804126
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In this thread, post real-life Viggen documentation such as flight manuals, maintenance manuals, instruction booklets, other military documentation such as reports, memos etc etc. I'll keep the OP updated with a list of documents. To get us started: Flight manuals and other official documentation AJ and AJS 37: SFI AJS 37 del 1 kap 1 (open, unclassified) SFI AJ 37 del 2 kap 1 (formerly classified secret) SFI AJ 37 del 3 (formerly classified secret) SFI AJ 37 del 2 kap 1 ändring 90 (pack of updated pages for SFI AJ 37 del 2 kap 1, formerly classified secret) Minnelista för ff i fpl AJS37 (memory items/checklists for AJS 37 pilots) Minneslista för ff i fpl 37 NÖD (emergency memory items/checklists for all Viggen variants except JA 37) JA 37: Aircraft JA 37 flight manual, volume 1 chapter 1 (English version of SFI JA 37C, unclassified part) SFI JA 37 del 4 (formerly classified secret) Non-specific: Aerodynamik fpl 37: kompendium (pilot's introduction to the Viggen's aerodynamics and its aerodynamical development history, formerly classified secret) Fpl 37 aerodynamik III: Manöverprestandabegränsningar, halvroll: kompendium (pilot's textbook on control surface performance limitations and split S performance, formerly classified secret) Anvisningar för typinflygning fpl 37, 1985 års utgåva (lesson plan for getting your type rating on the Viggen, ~45 flight hours total) Beskrivning bombkapsel M90 (technical description of the bk 90; open, unclassified) Technical reports, assessments etc NASA technical memorandum: aerodynamics of the 37 Viggen aircraft, part 1, characteristics at low speed Saab JA 37 Viggen Performance Assessment (made by an engineer but with limited resources and without access to the original documentation) Spinning the Viggen (article in a FlightGlobal issue from 1974) Doctrine, tactics, service history etc Med invasionen i sikte: en beskrivning och analys av flygvapnets luftoperativa doktrin 1958-1966 (Masters thesis in history; the doctrine analyzed predates the Viggen but it persisted largely unchanged when the Viggen entered service.) Taktiska anvisningar för attackförband, 1961 års utgåva (Tactical manual for A 32 Lansen squadrons; predates the Viggen but as mentioned the doctrine was similar.) Taktiska anvisningar för jaktförband, 1965 års utgåva (Fighter tactics manual for all kinds of fighter squadrons; again this predates the Viggen but tactics and doctrine remained similar for most of the cold war.) Tangentially related reading JA 37: Pilot och system Lärobok i telekrigföring för luftvärnet - radar och radartaktik (Telekri Rr Tak Lv, M7741-850101) Motmedel inom svenska flygvapnet 1950-2005 Anvisningar för telefonitrafik vid flygning Ammunitionskatalog, data och bilder: flygvapnet (1984) (catalog of all munitions used in the air force, from .22 training rounds to missiles and rockets; handy to have around as a reference)
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You get a minimum of 5 weeks (25 working days, that is) a year in Sweden, by law. Many companies offer more as a benefit. A lot of people take at least 3-4 uninterrupted weeks in the summer. It's not like the entire office goes off for three months at the same time, a lot of businesses slow down markedly during the summer months because important people go off and come back at different intervals. Nothing at all of import ever happens in the business world between Midsummer and the end of July.
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So do I, man, so do I. :(
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Doubtful. From my experience in software projects, nobody wants to release anything immediately before a vacation (or even a weekend). Something always goes wrong and needs to be hotfixed and that's hard to do if everyone just disappeared off to vacation. I strongly doubt anything will happen over summer. Hope for September I guess.
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Cobra mentioned somewhere that after the Viggen is announced things would calm down for them because they'd spend "months" on marketing. Unclear if that was referring to before or after release. I wouldn't expect any news at all until after summer, it's almost vacation season after all. In other news the national archives recently informed me that unfortunately they do not have the performance chart part of the SFI for AJS 37. Seems they never received a copy.
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It definitely is. I noticed one sentence when talking about Lansen countermeasures, namely: I'm pretty sure that refers to RT-02, a network of fixed jamming stations that was supposed to interfere with the Soviet equivalent of LORAN radio navigation - in the ideal case imitating the signals and faking them so well that the Soviet aircraft wouldn't notice that it was leading them wrong. Read that article, it's very interesting. Speaking of radar and ECM, if you're interested in the subject as a layman and want an accessible and reliable source to learn from, I highly recommend Lärobok i telekrigföring för luftvärnet: radar och radarteknik, which goes over all the elementary radar knowledge first (it's a very nice and pedagogical explanation and it's very nice to have it in Swedish) and then covers a lot of countermeasure methods in general terms. It is available for free online: [ame]http://www.luftvarn.se/hot/tklv.pdf[/ame]
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I interpret that as the lines falling over power lines by accident, short circuiting them.
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Well, you're right in practice. The RCS does matter, but from the radar equation it follows that while received power is proportional to the RCS, it is inversely proportional to R⁴ (where R is the range). Meanwhile, energy received from a jammer is inversely proportional to R² (since it doesn't have to bounce and come back - it's traveling only one way), and that's why the burn-through distance is a thing: energy received from the jammer falls off slower over range than energy received from echoes does. Furthermore, range tends to be three orders of magnitude larger than RCS (from around 1 m² to around 100 m² for RCS and from about 1 to about 100 km for range). In other words, as far as jammer power output requirements go, if you want to hide yourself, range is vastly more important than RCS. edit: to review the maths: Ps * G² * σ * λ² Pe = ---------------- (4π)³ * R⁴Where: Pe is the received power (in Watts) Ps is the transmitted power (in Watts) G is the antenna gain σ is the RCS (in meters squared) λ is the wavelength (in meters) R is the range (in meters)
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I have no idea if the numbers for the MiG-23 are accurate, but I translated a few climb and acceleration graphs from the AJ 37 flight manual (SFI) for those who do not speak ärans och hjältarnas språk. Since the graph labels are the same for all the graphs, if you want to go look up more numbers for other situations you can use these as a key. First, the aircraft loadouts are divided into five groups: clean aircraft with no external load (rent fpl), and four groups numbered 1 through 4. Loadouts that are representative for each group can be found in this table, which lists both aircraft weights and drag indexes: Note that 100% fuel means 100% internal fuel. If the drop tank is fitted, max fuel is 124%. To understand the leftmost column, use this key of abbreviations: Now, takeoff and acceleration to M 0.55 (distance-economical airspeed at sea level): Climb with clean aircraft: Climb with the heaviest and draggiest loadouts possible: If you want more graphs, see part 3 of the SFI.