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October 3, 2014 at 9:13 am in reply to: Eurofighter Typhoon Discussion and News 2014 #2219870

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My mystake, I found the source: http://uk.reuters.com/article/2014/10/01/austria-eurofighter-idUKL6N0RW3IF20141001

October 3, 2014 at 8:29 am in reply to: Eurofighter Typhoon Discussion and News 2014 #2219892

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Simply said: out of tolerances

Britain’s BAE Systems had identified drill holes “which do not meet design criteria”

Do you have any source for this information, I did not find that in any cited source here ?

September 10, 2013 at 1:31 pm in reply to: What are differences between Indian MiG-21M? and Soviet MiG-21MF? #2246085

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In the Yefim Gordon’s “Mig-21”, it is said that the HAF built Mig-21M (type 88) and the Soviet Mig-21MF (iz.96F) are “virtually identical: same engine (R13-300), same radar (RP-22), periscope….
To make it simplier (LOL), IAF also received 65 soviet Mig-21M (iz.96), but IAF named them Mig-21M…

So,
– what HAF/IAF call a Mig-21M (a type 88), is quite identical to the soviet definition of a Mig-21MF (iz.96F)
– what IAF call a Mig-21MF, is a a/c delivered by its sovient manufacturer as a Mig-21M iz.96

Concerning the Mig-21FL, in the same book they are said to be withdrawn from active service in 2005

September 2, 2013 at 5:04 pm in reply to: JUST A NICE PIC – Mirage III #2252411

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Yes, it was premature given that i havnt seen a pic yet, so i have no clue how much it is canted, or even if it is canted at all,
hopefully there is a pic somewhere. Still, at what speed was that drag comparison, and at what altitude ?
aam drag becomes insignificant at cruise speed, especially compared to the fighter induced drag.

Here is a comparison at M3 40.000 ft
For an AMRAAM like AAM going at high altitudes (40,000 ft)…
Drag Force @ Mach 3 = 0.5 x 0.232 x (295×3)^2 x 0.70 x 0.025 = 1590 Newtons = 357 lbs

Assuming the missile fly at 30* AoA during a turn at M3 & 40.000 ft, that is
Drag force (Newtons) = 0.5 x P x V^2 x Cd x A
0.5×0.232x783225x0.7xsin30(0.18×3.7)=20987 N, 4718 lbs
compare to 357 lbs in straight flight, some 12 times increase in drag, almost twice as much as the drag at low lv

OK, I misunderstood your statement…
I thought you said the drag of a R-550 is 5 time greater that the one of a AIM-9 WHEN BOTH ARE INSTALLED ON THE LAUNCHER/PYLON/PLANE… (And I stated I was suprised by this statement)
On the opposite, I do not have any idea about compared drag of AIM-9 and R-550 at other AoA, so I would not contradict you on that point.

September 2, 2013 at 2:43 pm in reply to: JUST A NICE PIC – Mirage III #2252520

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Do you have a pic example ?
On a hunch it is separation issues that forces the short-length big-fin Magic to be canted so as to not flip into the a/c at separation,
causing a drag at least 5 times greater than sidewinder

Stangely, in Mirage III-E performance sheets, fuel flow, range, endurance are said to be independant from R-550 or AIM-9 being loaded (same Drag index in US words for the 2 configurations).
With a DragIndex 5 time larger than the AIM-9 one, R-550 would have had a much-than-significant impact on these data.

August 30, 2013 at 5:17 pm in reply to: Question about versions of F-4 having slats or not #2254336

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If I refer to T.O. 1F-4C-1 published on the 15 AUGUST 1973 with change 1 (15 DECEMBER 1973) at page vi
the Technical Order 1F-4E-566 contains the following
ECP 7176 : Add leding edge slats
ECP 7191: Adds additional aural tone for leading edge slats aircraft
ECP 7087R2 : Adds AGM-65A missile capability
ECP 7151 : Adds multi sensor display group (MSDG)
ECP 7177 : Add target identification system electro optical (TISEO)

TO.566 is applied with production effectivity from F-4E #SN 71-237 and up (middle of the Block 48)
TO.566 can be partially applied (ECP 7176 and 7191 only) to all F-4E up to #SN 71-236 in retrofit.

The technical Order 1F-4E-556 contains 2 ECP
ECP 683R2: Improve conventional weapon capability and removes AFCS heading hold cutout capability, Production effectivity F-4E 71-224 and up, Retrofit Effectivity F-4E 66-284 to 69-7589
ECP 7143 : Adds flight instrument ligths control Production effectivity F-4E 69-7261 and up, Retrofit Effectivity F-4E 66-284 to 69-7260

BTW, you are right concerning the F-4EJ, they never receive TO.566 in retrofit and kept the regular F-4E slats (non leading edge one), coupled with flaps for take-off and landing purpose (when TO.566 leading edge slats are also called manoeuvring slats and their position driven by AoA)

August 30, 2013 at 5:05 pm in reply to: JUST A NICE PIC – Mirage III #2254343

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Also, is that last one a Mirage IIIA?

I do not think so, Mirage III A (the one I know the best are Mirage III-A-0 and Mirage III-A-2, but there were 10 built) are much closer to the final definition.
I would suspect this picture being one of the Mirage-III (sans suffix) also known as MD 550-03 fitted with an ATAR 101G (and not the ATAR-9 of the following Mirage-III A, B, C)

August 30, 2013 at 3:55 pm in reply to: Question about versions of F-4 having slats or not #2254430

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Answer came from C6 forum:
– F4-F may not have been equiped with leading edge slats when delivered, but should have been retrofitted with TO.566 later.
– F4-G have TO.566 leading edge slats installed on manufacturing line.
– F-4J have never been fit with leading edge slats (decision from NAVY to keep their speed, climb rate and range compatible with their “interceptor-of-the-fleet status)
– F4K and M (FG-1 / FG-R2) derived from F-4J have never been fit with leading edge slats.
– F4-N (modernized F4-B) have kept their original slats (not the leading edge one), but the internal one has been fixed up.
– F4-S (modernized F-4J) received leading edge slats, close to teh one installed on F-4E with TO.566.

March 5, 2013 at 2:39 pm in reply to: F-4E vs. Mirage F-1CT #2313555

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Wrong about the climb-rate. Maybe you had the Mirage IIIC in mind. 😉

And even in that case, it depends on what you call climb rate, the old Mirage IIIC has an instantatenous climb rate at sea level very close to the one of a F-4E Blk50 (But Ok, it takes more time to climb to FL360 without its SEPR rocket)

BTW, from what data can you claim the Mirage F1 climb rate being so mediocre ?

February 11, 2013 at 7:08 am in reply to: Room for a new type #2371929

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700Kts without A/B… would be great, but I doubt.

December 13, 2012 at 2:16 pm in reply to: Aerodynamic question #2274601

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And Mirage G M2.35…
The limitation of modern fighter such as Typhoon or Rafale to M2.0 (or 1.8) has nothing to do with stability, only with engines and air-intakes

September 24, 2012 at 6:34 pm in reply to: Gripen for Switzerland #2304850

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It will be difficult not to receive anything in the next 10 years since Gripen C/D will be supplied on a temporary basis. That fact means that there is virtually no risk that Switzerland will have to keep F-5 in service longer than planned due to delay in Gripen E/F arriving.

Seems I mad an error then…
Do you have an idea of the schedule for Gripen C/D delivery to Swiss AF, and do you know what will happen with these aircarfts when Gripen E/F will be delivered (in 2018/2023 I suppose), assuming that retrofit is not possible ? They will be send back to Sweden ?

September 24, 2012 at 7:07 am in reply to: Gripen for Switzerland #2304964

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That is actually more complex than the above. Maurer would have delayed the acquisition for a few years if possible (due to budget constraint), but the parliament forced him to make his choice as the offers wouldn’t be valid beyond the end of 2011.

You may be 100% right : Chosing Gripen E is the best choice if you do not want to receive anything in the next 10 years. The two others competitor would have been delivered (and paid) in a much shorter term.
Swiss had bought what they were looking for : time…

September 22, 2012 at 2:58 pm in reply to: Dassault Rafale #14 – News & Discussion #2305653

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Not exactly: As of today, no customer, neither prospect, actually ask for more thrust, but for extended servicability, this is what provide E4-GCP.
If someone ask for more thrust, SNECMA can make a proposal and claim it will not significantly reduce servicability (compared to E4-GCP).

September 17, 2012 at 7:02 am in reply to: Possible BAE/EADS merger #2308081

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As you say, main target of DI (DASSAULT INDUSTRY) is to make money, so no doubt they’ll keep DS in…
For DA, the question is ; is it possible to keep such a design office active with only BizJet revenues (quite a cyclic market), and keep an acceptable operational margin.
My opinion is that Military contracts, in smoothing design office load, are a key factor for DA margin.
In case of BAE/EADS merge, is there enough space in european A&D sector for DA to smooth its Design office load ?
I’m not sure the answer is no… and for the next 10 years, I’m sure the answer is still yes, but after ?
This is why I’m not optimistic concerning the future of DASSAULT AVIATION at long term if such a merge occurs (note that I have no doubt that DASSAULT INDSTRY will survive and grow, only DA)
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