Poslao: 28 Apr 2018 09:10
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- Toni
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Schwartz, in Memoir, Says F-22 was Traded for B-21 Bomber
Citat:In “Journey: Memoirs of an Air Force Chief of Staff,” now in bookstores, retired Gen. Norton Schwartz said his predecessor, retired Gen. Mike Moseley, “never gave up in his principled attempts to get those 381 F-22s,” for which Gates fired Moseley and the then-Secretary of the Air Force, Mike Wynne. Schwartz was named to replace Moseley, and Mike Donley was brought in as Wynne’s replacement.
Although there were at least a dozen internal and external studies confirming 381 as the right number of F-22s, “I wanted an independent assessment to determine the minimum number,” Schwartz wrote, “and what we came up with” was 243 aircraft. Gates rejected that number too, “even though we had shaved over 35 percent off the Moseley/Wynne demand for 381,” Schwartz said. That difference of 60 airplanes would have cost “$13 billion at a time that defense budgets were being tightened,” and Gates wanted that money for “things like remotely piloted aircraft and MRAPs.”
Schwartz and Donley concluded “the F-22 debate had consumed enough oxygen and it was time to move on,” Schwartz said, and the two were “certainly not going to go to the Hill behind Secretary Gates’s back and lobby for more … That was never going to happen on our watch.” Schwartz acknowledged that some thought this “too pristine a judgement,” and that “anything in Washington is fair, but I say no. I had never been disloyal to a boss and I wasn’t about to start then.” Schwartz wrote extensively in the book about how Gates fought for Schwartz’ nomination to be Chief against congressional resistance.
Gates, in his own memoir, “Duty,” argued that the F-22 was useless in the Afghanistan and Iraq counterinsurgencies, was a Cold War relic, and that a Chinese stealth fighter wouldn’t be along until the 2020s, so nothing would be lost by killing it. In actual fact, the F-22 has been essential in the Syria campaign and China fielded its first operational stealth squadron in 2017. Every Air Combat Command chief since Gates tenure has warned that the F-22 force is far too small for the demands placed on it.
http://www.airforcemag.com/Features/Pages/2018/Apr.....omber.aspx
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Registruj se da bi učestvovao u diskusiji. Registrovanim korisnicima se NE prikazuju reklame unutar poruka.
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Poslao: 28 Apr 2018 11:52
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- Leonardo
- Moderator u penziji
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Interesantno je posmatrati te velike sisteme kako se šutiraju u sopstvenu guzicu i pokušavaju reagovati na promene. Pogotovo kad se ima para ispratiti trenutni izazovi.
Relikvija Hladnog rata, koja je sad jedini odgovor na rastuću moć nekih zemalja.
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Poslao: 05 Maj 2018 11:46
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- Toni
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F-22A Production Restart Assessment
https://www.documentcloud.org/documents/4452474-F-.....sment.html
Citat:Working primarily with RAND's conclusions from 2011, the Air Force crafted the following cost estimates and assumptions for what it would take to restart F-22 production and produce 194 additional Raptors:
-Total non-recurring start-up costs over a five year period totaling $9.869 billion in 2016 dollars, equal to more than $10 billion in 2018 dollars at the time of writing.
-This included approximately $228 million to refurbish production tooling, $1.218 billion to requalify sources of components and raw materials, $5.768 billion to redesign four subsystems, and $1.156 billion in other associated “restart costs,” along with $1.498 billion in “additional government costs.”
-Two of the four subsystems needing "redesign" would be the AN/APG-77 low probability intercept (LPI) radar and the F119 engine, neither of which are still in production.
-The other two were the aircraft’s software package and an unspecified fourth system, acting as a placeholder to hedge against the Air Force discovering that other systems needed replacement during the restart process.
-The aircraft’s electronic warfare, communication, navigation, and Identification Friend or Foe (IFF) systems were among those that might also need replacement or substitution with another system.
-While the 2011 RAND study estimated an average unit cost of $266 million, this was based on a total purchase of just 75 aircraft.
-The Air Force estimated that the initial unit cost for an order of 194 aircraft would be approximately $216 million.
-This would drop to around $206 million by the time the last one rolled off the production line.
-The unit price would begin to largely level out after the service had purchased the first 100 aircraft.
- The total procurement cost would be between $40 and $42 billion, with the entire program costing a little more than $50.3 billion.
The Air Force also noted that while approximately 95 percent of the F-22-related production tooling is still available, the physical productions facilities either no longer exist or are supporting other Lockheed Martin programs, such as the F-35. After the 2011 study, the service elected to put the "primary production tooling" into a warehouse at Sierra Army Depot in California in case there was a need to make certain spare parts in the future.
Pratt and Whitney, who supplied the F119 engine, had also shifted significant focus to building the F135 engine for the Joint Strike Fighter. The F135 is developed from the F119 to some degree, though.
http://www.thedrive.com/the-war-zone/20633/exclusi.....ver-a-year
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Poslao: 22 Maj 2018 10:28
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- Kaplar
- Super građanin
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Baš bih voleo da pročitam neko mišljenje vezano za sliku, a naročito aerodinamiku koliko je optimalna za vertikalne i horizontalne manevre u poređenju sa Su-27 familijom.
Ima li neki stručnjak iz aerodinamike?
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Poslao: 30 Maj 2018 16:47
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- djox
- djox
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Sklonjeni zbog uragana...
Citat:"Рапторы" в гнезде.
Авиабаза Tyndall в ожидании урагана Альберто
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Poslao: 30 Maj 2018 19:57
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- Leonardo
- Moderator u penziji
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Kaplar ::Baš bih voleo da pročitam neko mišljenje vezano za sliku, a naročito aerodinamiku koliko je optimalna za vertikalne i horizontalne manevre u poređenju sa Su-27 familijom.
Ima li neki stručnjak iz aerodinamike?
Roll - valjanje -> nisam tražio podatke za oba aviona. Recimo :
Citat:Although the roll rate depends on the configuration, weight, speed, altitude and the fact the rate is measured from stable flight (instantaneous roll rate) or after the rotation has been given some time to build up (i.e. the aircraft keeps on rolling long enough), the maximum roll rates for some of the most famous combat planes can be either found on vendors datasheets or online (hence, take them with a grain of salt): according to most reports a Rafale features a maximum roll rate of 270 deg/s, the Eurofighter Typhoon is able of around 250 deg/s, the F/A-18E Super Hornet has a maximum roll rate of 120 deg/s whereas the F-16 can roll at 240 deg/s.
Pitch - propinjanje -> F-22 bilo gore ili dole nešto bolji.
Yaw - skretanje -> takođe ne znam.
Brzina penjanja bi trebala biti veća za F-22, ali je pitanje kolike su im kad se popune gorivom i naoružanjem.
Postoje mnogi manevri, pogotovo u horizontali gde Su-35 deluje življe i brže, te daje nešto bolji.
Suštinski nema pravog takmičenja. Koliko F-22 ima prednost da prvi uoči i započne susret BVR raketama, tako Su-35 ima šanse da izdominira u završnici. Kad se na kraju uporedi broj operativnih, ukupan nalet i intezitet treninga, broj pilota itd. prednost je na strani F-22.
Meni je koncept F-22 bliži "srcu", te prvenstveno YF-23 i Su-57.
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Poslao: 30 Maj 2018 21:20
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- ltcolonel
- Stručni saradnik foruma
- Nebojša Đokić
- vojni istoričar
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- Gde živiš: Novi Beograd
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Prema onom što pričaju i pišu zapadni piloti koji su leteli protiv F-č22 reč je prilično lošem avionu po manevarskim karakteristikama. Interesantno je da postoji konsesus među svim NATO pilotima koji su leteli protiv F-22 da bi on bio vrlo lak plen u u bliskoj borbi i Rafalu i Tajfunu. Naročito je karatkeristično to da svi uglas tvrde kako je reč o vrlo tromom avionu kome treba dosta vremena da reaguje na komande u dog fajtu. Piloti na Tajfunima su na ono nekoliko održanih vežbi bili šokirani koliko F-22 ima loše manevarske osobine.
Što se tiče borbe na velikim daljinama. Stvarno ne znam koje su karakteristike raketa AIM-120D (njih ni ne može da koristi F-22) ali rakete AIM-120C bilo koje verzije ne omogućavaju vođenje vazdušne borbe, protiv manevarskih ciljeva na daljinama većima od 35 km (a i to je pitanje). Nemoj niko da vas laže. Priče o 60, 70 i više kilometara su bajke za malu decu. Pa sve verzije rakete AIM-120 na daljinama preko 60 kilometara su dozvučne tj brzina im pada ispod 1 maha a dozvoljeno preopterećenje na 3 do 4 g.
Ni za jedan avion se ne laže toliko koliko za F-22. Ako za njega vrede zakoni aerodinamike on mora da ima loše manevarske karakteristike. Doduše, za Amere zakoni aerodinamike ne važe već zakoni Hari Potera.
Za one koji ne veruju. Nagradno pitanje. Kolika je brzina sletanja aviona F-22 i koji je napadni ugao pri prilaženju za sletanje. Taj podatak nećete naći nigde - čak ni brzinu sletanja. Jer kad bi to objavili skinuli bi gaće i ceo svet bi znao da im ona stvar i nije baš nešto ...
PS. Po nezvaničnim podacima koji kruže po ZAPADNOJ štampi njegove karakteristike pri sletanju odgovaraju avionima F-104 i F-105 i lošije su od F-4.
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Poslao: 31 Maj 2018 03:37
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- miodrag2
- Počasni građanin
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Lt, secam se clanka o programu ATF iz Glasnika RV i PVO, u godinama neposredno pred raspad bivse SFRJ (tedoh da napisem pred raspad zemlje, a onda se setih da smo mi u Srbiji doziveli vise tih raspada).
Clanak je bio opsiran, i ako se dobro secam napisao ga je Angel Oncevski. Tako da nije bio neko nestrucno naklapanje.
Tu je program bio analiziran na nekih 5-10 strana, sa naglaskom na kraju na sam F-22, posto je on prosao na konkursu.
Zahvaljujuci tome autor je imao mesta i za citate Lockheed-ovih inzenjera.
A oni su rekli da je konfiguracija F-22 na kraju bila kompromis izmedju dijametralno suprotnih zahteva, koji su omogucili zadovoljenje takticko tehnickih zahteva, ali zato ostetili avion u pojedinim delovima anvelope leta. Secam se da je naglasak bio na velikoj povrsini krila, radi smanjenja specificnog opterecenja krila, ali je ista izazvala i povecanja inercije tokom manevara u kojima je zahtevano okretanje aviona oko uzduzne ose.
Postavljanje vektora potiska u jednoj ravni je na kraju bilo nuzno ne zbog karakteristika u post stall manevrima, vec zbog postizanja odgovarajuce manevrenosti koja bez datog vektora potiska ne bi bila na zadovoljavajucem nivou.
Bilo je tu dosta toga, analiza je, s obzirom ko je pisao clanak, bila detaljna. Ja danas posle skoro 30 godian ne mogu da se setim svih detalja, a taj primerak koji sam imao je u jednom od ciscenja viska materijala iz sobe otisao u pec. Ali, ako se neko od forumasa seca ovog clanka, i ako ga jos bolje ima ovaj primerak Glasnika RV i PVO, bilo bi dobro da ga skenira i postuje. Bilo bi vrlo zanimljivo za kolege forumase da procitaju sta je u to vreme Oncevski napisao, a pogotovu citate inzenjera iz Lockheed-a i McDonnell Douglas-a.
To bi uveliko i potvrdilo tvoju tvrdnju u ovom postu.
U nekom od tih glasnika iz 1990.-91-ve je bila i analiza programa EF-2000, kao i odabira rakete srednjeg dometa za isti. I tu je precizno objasnjeno zasto se uslo u program Meteor rakete, sta je to sto je nagnalo pre svega Britance da procene da su tadasnja AIM-120C i MICA neefikasne u borbi na srednjim udaljenostima protiv MiG-29 i Su-27 (sto je praksa i kod nas pokazala, koji god je MiG-29 imao ispravan SPO uspeo je da izbegne sve lansirane AMRAAM-ove), i da se odluce za ulazak u program razvoja Meteor-a, a da AIM-120C usvoje kao privremeno resenje do zavrsetka razvoja Meteor-a.
To bi objasnilo i mnogim usijanim glavama ovde zasto su njihove price o dometima pojedinih raketa, lansiranju istih u ovim ili onim rezimima, itd, teske gluposti, kao i zasto ti tvrdis (a to tvrdim i ja sa razlogom) da je maksimalna daljina lansiranja AIM-120C 30km ako se zeli verovatnoca unistenja cilja od barem 50%. Veci postotak unistenja zahteva jos manje daljine lansiranja. Slicno vazi i za raketu MICA, slicno vazi i za R-77, ali i za sve poluaktivno vodjenje rakete u naoruzanju bilo kog RV.
Tako da ako neko od kolega forumasa ima ove Glasnike, i ako moze da nadje clanke, bilo bi dobro da ih skenira i postavi, da bi se neke glave ohladile, i malo spustile na zemlju.
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