sebab ::nisam siguran da je sve tako "linearno". ne bih iskljucio da su neka iskustva sa yf23 primenjena na yf22. pitanje je i kolika je razlika u steltnosti izmedju yf23 i yf22.
Kao sto kazes, cini se da se deo resenja YF-23 primenio i na F-22. Produzena su mu krila (raspon je povecan) da bi se jos poboljsale manevarske osobine. Smanjen je napadni ugao ivice krila u odnosu na YF-22, pa je dobijeno nesto pribliznije YF-23, radi povecanja steltha.
Citat:koliko se secam yf22 je pobedio zbog boljih manevarskih osobina.
I ja sam tako cuo.
Besotted,
Koliko znam i YF-23 je imao TVC. Ali neki polu 2D, mogao je da vrsi otklon samo na gore. Po svemu sto sam do sad nasao, letno nije bio bolji od YF-22, pa samim tim tek ne moze biti ni od F-22, dok je po stelthu bio napredniji ali ne znam koliko.
Ono sto si naveo za sletanje u UK je vrlo interesantan podatak i voleo bi da je tacan, stvarno. Steta bi bilo da avion (koji meni nije bas lep) koji ima svojih kvaliteta i potencijala ostane neiskoriscen. Po meni su mogli da ga neiskoriste jedino ako su budale, makar u nekoj manjoj seriji.
Ja ga ne vidim tako kao ti, kao air-dominance fighter ali ga vidim kao idealnu zamenu za F-117 sa mnogo boljim letnim karakteristikama. Jedino ako u pricu nije upao Bird of Pray kao zamena za Night Hawk-a.
zgembo,
Malo mi je cudno ono sto si naveo da je razlog njegovog neizbora to sto je bio presavrsen i da preskace jednu generaciju, pa bili bi ludi ta tako nesto odbace.
On je bio light years ahead sto se kaze.. Zaista je bio tehnoloski napredniji sto aerodinamikom i samim izgledom a sto performansama pri transonicnim i vecim brzinama. Ljudi se boje velikog rizika i nepoznanica. To je nekako normalno. Stariji su ljudi Kongresmeni a oni ne vole velike promene ili ikakve kao sto znas od ljudi okolo sebe.
Malo mi je cudno ono sto si naveo da je razlog njegovog neizbora to sto je bio presavrsen i da preskace jednu generaciju, pa bili bi ludi ta tako nesto odbace.
Pa rekao sam da moze biti pretjerivanje, jer o YF 23 stvarno znamo tako malo, ali po meni ima logike jer ne zaboravi da je amerikanac kapitalista u prvom redu pa sve drugo... kao i druge zemlje NATO-a, mozes zamislit ekonomsku stetu na projektima rafala, EFA-e, itd ko ce ga kupiti, ako imas u startu dvije generacije aviona ispred tebe...Mozda je doslo do kompromisa nekog izmedju saveznika, jer se sjecam clanaka koji kritiziraju evropske proizvodzace aviona koji nisu isli linijom kao amerikanci, nego imali svoj put...Kako sto rekoh u to doba Stealth je bio nesto novo...
Bas evo ponovo odgledah neke materijale o YF-22 i YF-23. I opet ne mogu da se nacudim kako bi YF-23 mogao biti bolji (kako se spominje negde), za razliku od Besotteda, po kome je ocito "udovica" bila favorit. Zbog oblika mu je stelth sigurno bio veci i brzina (koja danas nije bitna kao nekad) ali da je bio ukupno bolji, prosto mi neide u glavu. Jos me cudi ono sto je zgembo naveo, izjavu Americkog glavonje da je bio presavrsen?
Evo ti malo vise razloga da prestanes lupati glavu...za ono sto tvrdim ako ce pravo mozda se neke greske oko nabavke aviona i otklone i ponude ga u drugoj formi....Sorriram za engleski, nadam se da nije frka
01 Mar 2005
The outline shape of Northrop Grumman's proposed F/B-23 "regional" bomber concept may have been revealed inadvertently in the form of a desk-top model recently advertised on eBay, the on-line auction house.
The model, which was suddenly withdrawn from sale on 23 February, is dubbed F/B-23 RTA (Rapid Theater Attack), and is therefore believed to relate to earlier concepts predating the US Air Force's more recent long-range-strike studies. However, the overall configuration retains the basic rhomboid wing, and outward- canted empennage of the baseline YF-23A, in addition to an enlarged fuselage that forms the basis for Northrop Grumman's interim bomber proposal.
Other features of the model that may distance it from the YF-23-based actual proposal include axisymmetric engine nozzles and larger, semi-circular engine inlets.
Northrop Grumman declines to comment on the model, or its appearance, but confirms continued pursuit of USAF bomber studies and says "we are definitely interested in all those possibilities".
The model's appearance coincides with the decision by the USAF's Air Combat Command to launch an analysis of alternatives (AOA) around the third-quarter of 2005 that could lead to a competitive development programme for an interim long-range-strike aircraft.
The revised USAF plan indicates an 18-month AOA phase, leading to the creation of a capabilities development document by the end of 2007.
This could pave the way for a later system development and demonstration phase aimed at 2018 initial operating capability.
The 2006 USAF budget includes money for the regional bomber study work, but there is currently no additional funding in the service's five-year budget plan. Another issue is that the Lockheed Martin/Boeing F/A-22, which forms the basis for a potential proposed F/B-22 interim bomber variant, is likely to be out of production by then under the current budget plans.
The long-abandoned YF-23A Advanced Tactical Fighter emerged as the possible basis for a surprise contender for the USAF's interim bomber requirement last July when Northrop Grumman retrieved the second of the two YF-23A "Black Widow II" prototypes from the Western Museum of Flight in Hawthorne, California. The move, made ostensibly for repainting for display at an air fair that August, also included several cosmetic modifications believed to be linked to the bomber bid.
Under the original timetable, the interim bomber was intended to bridge the gap between the current bomber fleet and a next-generation aircraft planned for 2037. The present timetable calls for IOC by 2018 rather than 2015.
YF-23 re-emerges for surprise bid
13th - 19th Jul 2004
Northrop Grumman's "forgotten" advanced tactical fighter leaves museum and could be heading for bomber contest
Northrop Grumman's long-abandoned YF-23A advanced tactical fighter (ATF) is emerging as the possible basis for a surprise contender for the US Air Force's interim bomber requirement.
The company recently retrieved the second of the two YF-23A "Black Widow II" prototypes (PAV-2) from the Western Museum of Flight in Hathorne, California, ostensibly for repainting for display at a forthcoming Northrop Grumman-backed air fair in August. However, the restoration is also thought to include several changes, including new cockpit displays and other possible cosmetic modifications.
Northrop Grumman confirms restoration of the General Electric YF120-powered PAV-2 is taking place, but declines to comment on whether the revived YF-23A is linked to any USAF proposal. But sources close to the studies, which were kicked off by the USAF's recently issued request for information, say Northrop Grumman now includes a YF-23-based "regional" bomber concept among its raft of proposals and that the USAF "is interested".
Until now, the company's offerings are known to include an upgraded B-2, X-47B unmanned combat air vehicle (UCAV) -based studies and possible designs based on its quiet supersonic technology programme. The distinctive, rhomboid-winged YF-23A lost out to Lockheed Martin's YF-22 in the ATF competition in 1991, but proved a valuable technology testbed for Northrop Grumman, which gave it all-aspect stealth. The company says it "drew upon a wide range of experience for its response to the interim bomber RFI, and the YF-23 is one".
Other contenders include a Boeing's B-1R (regional) re-engined bomber studies and a larger D-model version of its X-45 UCAV, while Lockheed Martin is considering various derivatives of the F/A-22. These include single- and two-seat, re-winged and tailless versions dubbed the FB-22, the larger of which would be able to cruise at Mach 1.8 and have 75% of the range of the B-2 carrying up to 30 115kg (250lb) small-diameter bombs. Lockheed Martin is also understood to be offering a variety of other manned designs, including a flying-wing concept.
The interim bomber is intended to bridge the gap between the current bomber fleet and a next-generation aircraft planned for 2037. The present timetable calls for a development effort to start in 2006, with an initial operating capability by 2015.
Pa otprilike je bas to ono sto sam naveo, za sta mislim da bi bio odlican. Ali ne vidim poentu uvodjenja nekog novog aviona sa posadom u tim godinama. Mislim da ce se do tad prevazici svi problemi vezani za bespilotne borbene avione, sto avione koji su nasledestvo ovog vremena ili proslog (90'), cini nepotrebnim. Meni bi bilo mnogo normalnije da su od njega vec napravili zamenu za F-117, opet ponavljam, ako se kao zamena ne planira i radi na avionu Bird of Pray. Negde sam citao da postoji dokument i patent za njega, sto znaci da se nesto radi. On bi trebalo da bude kombinacija super manevarbilnog i super brzog aviona, sto bi trebalo da mu se omoguci sa promenjljivom-negativnom geometrijom krila (kombinacija saznanja dobijenih iz F-14 i X-29). Ako se dobro secam i ovaj projekat nosi potpis Nortropa.
Malo o testovima YF-23 za ATF nadmetanje
Citat:Northrop did not plan to do high-angle of attack maneuvers with the prototype, nor did it intend to fire any missiles. However, wind tunnel tests at NASA Langley showed that the aircraft could perform tail slides and had no angle of attack limits and could self-recover from any spin except in those situations when the weapons doors were open.
mean_machine ::Malo o testovima YF-23 za ATF nadmetanje
Citat:Northrop did not plan to do high-angle of attack maneuvers with the prototype, nor did it intend to fire any missiles. However, wind tunnel tests at NASA Langley showed that the aircraft could perform tail slides and had no angle of attack limits and could self-recover from any spin except in those situations when the weapons doors were open.
Znaci bio je prirodno stabilan avion ako sam ja ovo dobro razumeo. Svaki avion koji nakon uznemirenja recimo turbulencijom tezi da se vrati u prvobitan polozaj je staticki stabilan, tako nekako mu dodje definicija.
To samo znaci da je imao tako dobro ponasanje u letu da se sa lakocom vracao iz bilo kog spina u koji bi ga bacili namerno i da se odlicno pokazao.
Inace je bio full FBW i nije bio staticki stabilan.
Besotted ::To samo znaci da je imao tako dobro ponasanje u letu da se sa lakocom vracao iz bilo kog spina u koji bi ga bacili namerno i da se odlicno pokazao.
Inace je bio full FBW i nije bio staticki stabilan.
Sad si me skroz bacio u rebus, avion koji se kontrolise pomocu kompa, prirodno je nestabilan i takav avion ne tezi da se vrati u normalu.
Evo nekoliko definicija (sad nisam pisao iz glave):
- Avion koji je po prirodi stabilan ce sam po sebi imati tendenciju vracanja u pocetno stanje posle bilo kakve pobude
- Kada je avion pobudjen iz mirnog pravoliniskog leta kaze se da je stabilan ukoliko se vrati u svoj originalan polozaj bez pomoci pilota
- Tendencija aviona da razvije sile koje ga vracaju u prvobitan polozaj, kada je pobudjen iz pravoliniskog mirnog leta je poznata kao stabilnost
- Tokom manevra ako je avion dostigao mali napadni ugao i ako se avion vrati u horizontalni polozaj bez dodatnih pokreta komandi , onda je staticki i dinamicki stabilan
