If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
|
#1
|
|||
|
|||
Thank You,
do you have data about how long Mig-25 could keep max speed (and how much it was) in recon configuration? "Venik" wrote in message ... Vello Kala wrote: Aircraft Speed Altitude Mach Number SR-71 Blackbird 2,275 mph (3,660 km/h) 80,000 ft (24,385 m) Mach 3.35 MiG-25 2,110 mph (3,390 km/h) 42,650 ft (13,000 m) Mach 3.2 This data is from Aerospaceweb. Question: SR-71 looks like alien plane, have very special design (incl tanks what start to keep fuel on flight only)etc etc. Mig-25 looks as pretty usual plane. But difference in speeds is relative minor, expecially if to look at what altitude it is reached. How it is possible? Do anybody have more data? Say, about SR-71 performance at 40 000 feet? I don't think that comparing MiG-25 to SR-71 is entirely inappropriate, considering that the Blackbird was one of MiG-25's primary targets and both aircraft were designed for high-speed, high-altitude recon roles. MiG-25 was designed as an interceptor and in this role it has outstanding performance. MiG-25 can be compared to SR-71 in terms of performance needed to intercept the Blackbird. MiG-25 certainly had the right performance for that. MiG-25 was also designed as a recon plane and in this role it can also be directly compared to the SR-71. And some comments about the comments in this thread. MiG-25 is not made of stainless steel but of nickel steel alloy similar in composition to the nickel alloy used for X-15. The Valkyrie, on the other hand, was made of predominantly stainless steel. Operational requirements for MiG-25 differed drastically from those of SR-71. MiG-25 was designed to operate as any other Soviet fighter aircraft without any specialized facilities. This was also a factor in the choice of airframe design and construction materials. Nickel steel alloy used in MiG-25 construction does not carry a strength penalty when compared to titanium. MiG-25 was build to have an exceptionally strong airframe. One must not forget that MiG-25 had to meet a substantially higher level of airframe stress requirements than SR-71. MiG-25 was a mass-produced combat aircraft (a total of 1,186 were manufactured), while the total production run of the entire A-12/YF-12/SR-71 line was only 49 aircraft or so. Design of the MiG-25 started in 1959 as the Ye-155P (http://www.aeronautics.ru/mikoyan/mig25_31/page_10.htm) multi role interceptor. The Ye-155P was not being developed specifically to counter the A-11/A-12, although the Soviets knew about this project and about its performance requirements. Intercepting low-flying cruise missiles, for example, was one of the roles for the Ye-155P from the very beginning. At the time the Soviets were concerned with the US and British advances in cruise missile development - Regulus, Rascal, Blue Steel, all of which had Mach 2++ capability. The late 1950s and the early 1960s was a time of particular Soviet obsession with heavy interceptors. During this period USSR produced several aircraft of this type, including La-250, I-75, Ye-150/152, Tu-128. Various Russian publications indicate that the Soviets learned about the A-11 project sometime in the summer of 1960. The Ye-155 project got its official Central Committee go-ahead in 1961, so it seems like there is a clear link between the two aircraft but there isn't one. Soviets learned about the A-11 in 1960, while the work on the Ye-155 concept begun in 1959. In any case, even in 1960 Soviets had only a rough idea of the expected performance of A-11/12, which, at best, was one of the reasons for the Ye-155's expeditious approval by the Central Committee in 1961 but not for the aircraft's concept. The B-58 became operational, the XB-70 was in development, the A-5 flew in 1958 and it is believed that Mikoyan was particularly impressed by this aircraft. In other words, there were plenty of real threats justifying the development of the Ye-155 other than the A-12, which in 1959 existed only in the form of a diverse collection of wind tunnel models. I read Belyakov's book, where he mentions Soviet knowledge of the A-11 program. However, the immediate question in my mind was: why would it appear so critical of a threat to the Soviets to prompt a massive development effort of an advanced interceptor as Ye-155? The Soviets became aware of the Suntan project prior to the A-11. They were aware of the Valkyrie. The Ye-155 itself seems closer in design to the A-5 than to A-11. At that time the PVO wanted an interceptor, while the VVS desired a new recon plane. The very fact that a decision was made to combine these two requirements in a single aircraft clearly shows that the Ye-155 could not have been created to counter specifically the A-11. -- Regards, Venik Visit my site: http://www.aeronautics.ru If you need to e-mail me, please use the following subject line: ?Subject="Newsgr0ups resp0nse" |
#2
|
|||
|
|||
Vello wrote:
Thank You, do you have data about how long Mig-25 could keep max speed (and how much it was) in recon configuration? With a drop tank MiG-25RB can maintain Mach 2.35 for about 80 minutes. You can view the basic performance numbers for the RB model here (PDF, 120kb): http://www.aeronautics.ru/archive/pd...erformance.pdf (from "MiG-25 Foxbat", by Yefim Gordon). The speed record set by E-266 in 1967 on a closed 1000km course with 2000 kg payload was 2920.67 km/h. Same year this plane set the speed record on a closed 500km course with 2000 kg payload - 2981.5 km/h. The SR-71 could not beat the speed records on the 100km and 500km closed circuit courses due to it limited G-load capability. The E-266 also set the absolute altitude record with 2000 kg payload in 1977 - 37800 meters (124000 ft), while the SR-71 holds the altitude record in horizontal flight - 25950 meters. MiG-25's maximum speed was capped at about Mach 2.83. This was an artificial limitation designed to reduce the risk of control problems. Here are a few related excerpts from Yefim Gordon's book on the MiG-25 (please excuse the OCR errors): pp. 32-33 -------------------------------------------------------------------------- MiG-25M (Ye-266M) Development The 1972 directive ordering the service entry of the MiG-25RB, 'RBK and 'RBS also elaborated on the upgrade possibilities of the basic de- sign. The military wanted an increase in range at low and medium altitude and an increase in ceiling and maximum speed. The Mach 2.83 speed limit imposed on the MiG-25 was purely theoretical, since the aircraft had the potential to go faster from the very start. High speeds reduced lateral stability and ser- vice life, but there were cases of pilots exceed- ing the speed limit without harming the aircraft. Therefore, the designers intended to reach a Mach 3.0-3.2 top speed so that the MiG-25 could outperform its arch-rival, the SR-71A - the world's fastest recce aircraft. This could be achieved by fitting the MiG-25 with more pow- erful and fuel-efficient engines. As far back as the early 1960s, a group of engine designers led by Shukhov and Rot- mistrov proposed a comprehensive upgrade of the R15B-300 turbojet. The idea materialised as the uprated R15BF2-300, Izdelye 65M. The improvement in performance was achieved by adding a compressor stage and increasing the combustion chamber and turbine tempera- tures. As compared with the R15B-300, the R15BF2-300 had a lower specific fuel con- sumption, a higher thrust (10,000kgp/22,045lb st dry and 13,230 to 14,500kgp/29,166 to 31,966lb st reheat) and a higher compressor pressure ratio (4.95 vs 4.75). The two engines were perfectly interchange- able, having identical dimensions and mount- ings. Providing the airframe was made more heat-resistant (that is, because of the higher turbine temperature), the new engines offered a substantial increase in rate of climb, ceiling, range and speed (up to 3,500km/h, or 2,187mph). The Mikoyan OKB started a massive research effort with a view to increasing the MiG-25's top speed, concentrating mainly on aerodynamic stability and airframe/engine thermal limits. The aircraft's principal structure was made of steel and thus was heat-resistant enough. Some parts of the airframe, however, such as the radome and forward fuselage, wingtips, flaps and ailerons, were made of Duralumin and plastics. They were not subjected to significant structural loads but experienced high tempera- tures and had to be replaced with steel or titani- um honeycomb structures. This, in turn, called for new technologies, Therefore the Mikoyan OKB suggested to split the work into two stages, ie, test and refine the engine on a struc- turally standard MiG-25 first and come back to the speed issue later. Both the WS and the Ministry of Aircraft Industry went along with this approach and gave the go-ahead for Stage 1. In September 1964 the Ministry issued a directive detailing the test programme of the re-engined MiG-25. Yet the theoretical part, manufacturing and bench testing of the R15BF2-300 took longer than predicted, and flight tests did not begin until 1973. The VVS initially allotted a single MiG-25 for test purposes, which was later joined by a second aircraft. Aircraft No.1 was a MiG-25RB which was given a new factory number (f/n) 02-601, after being modified (hence the tactical number 'Blue 601'). Aircraft No.2 was a standard MiG- 25PD built in 1973 (f/n 84019175) which made its first flight with standard engines on 12th June 1973 with Ostapenko at the controls. (Later it was flown by Fedotov, Fastovets, Orlov and others.) On 30th August 1973 the aircraft received its intended R15BF2-300 engines, a new c/n (841710) and the tactical number 'Blue 710'. From then on, the two aircraft served as test- beds for the new turbojet with the provisional designation MiG-25M (Modifitseerovannyy - modified). The conversion work was complet- ed very quickly but refining the engine took a considerable time. Still, it was worth the sweat: the enginedidproduce the claimed perfor- mance. The service ceiling exceeded 24,200m (79,396ft) and supersonic cruise range was 1,920km (1,200 miles) in clean condition or 2,530km (1,581 miles) with a 5,300 litre (1,177 Imp gallon) drop tank. The modified MiG-25RB was used to set a number of world time-to-height and altitude records. On a single day (17th May 1975) Fedo- tov and Ostapenko set three time-to-height records, reaching 25,000m (82,020ft), 30,000m (98,425ft) and 35,000m (114,829ft) in 143.2 seconds, 189.85 seconds and 251.7 seconds respectively. For these record flights the aircraft were designated Ye-266M for FAI registration purposes and had all non-essential equipment removed to reduce weight. Same year the interceptor, 'Blue 710', was further modified by fitting the wings of the recce aircraft ('Blue 601') and new stabilators previ- ously tested on another development MiG-25 ('Blue 502'). More modifications followed in 1976, this time to the electrical and control sys- tems. The aircraft was used as a test-bed until withdrawn from use in April 1977. The modified recce aircraft continued flying for some time. In the summer of 1977 Fedotov bettered his own altitude world records. On 22nd June he took the aircraft to 37,800m (124,015ft) with a 2,000kg (4,409lb) payload, and reached 37,650m (123,523ft) on 31st August with no payload. However, soon after the record flights, a pressure valve in the fuel system failed in a regular flight, causing one of the fuselage fuel tanks to get overpressurised and burst. A good-sized portion of the upper fuselage skin came off in mid-air; test pilot A G Fastovets displayed no mean skill and bravery, managing to land safely. The aircraft was repaired but test flights did not resume. The test flights of the re-engined MiG-25Ms confirmed the possibility of improving the air- craft's performance considerably. In lightened form for the record breaking flights the aircraft had a thrust to weight ratio better than 1:0 for the first time in Mikoyan OKB history. As a result, the brakes could not hold the aircraft in full afterburner, and a special mobile detent had to be developed (a heavy vehicle with a jet exhaust deflector to which the aircraft was con- nected by a strong cable and lock). The re-engined MiG-25 never entered pro- duction - for several reasons. First was the test programmes of two new aircraft, the MiG-25 Izdelye 99 and the MiG-31, which also began in 1975. Both aircraft were powered by the Solov'yov PS-30F (D-30F) engine with a similar rating but a lower specific fuel consumption (SFC). Second, the aero engine factories were tied up with other orders and could not produce the R15BF2-300. Finally, the PVO top com- mand was more interested in the MiG-31 than in an upgrade of the existing MiG-25. There- fore, the MiG-25 programme was terminated. Shortly afterwards the modified MiG-25PD ('Blue 710') was transferred to a school for junior technical staff, acting as a ground instructional airframe for a while. Later it was transferred to Moscow-Khodynka and is now on display at the open air museum there (inci- dentally, displaying its original construction number). ------------------------------------------------------------------------------ p. 37 ------------------------------------------------------------------------------ MiG-25PA(Ye-155PA) Interceptor In the mid-1960s the Mikoyan OKB was work- ing on an interceptor project referred to as the Ye-155PA. This aircraft was to be capable of destroying targets flying anywhere between 100 and 30,000m (328 - 98,425 ft) at speeds of 3,500 to 4,000km/h (2,187 - 2,500 mph). To this end, it was to be equipped with the brand-new 'Smerch-100' radar, later renamed 'Zaslon' (Shield), and armed with the equally new R-100 missiles. The powerplant consisted of two R15BV-300 turbojets with an improved high altitude performance (Vysotnyy - high altitude) which would take the aircraft to Mach 3.5. Later, the requirements changed, especially regarding speed, and the project was discon- tinued. As for the radar, a refined version (SBI- 16 'Zaslon') was later installed in the MiG-31. ------------------------------------------------------------------------------ p. 49-50 ------------------------------------------------------------------------------ The MIM-23 Hawk missiles used by Israel were no great threat to the MiG-25 either, since the aircraft was out of their altitude range (12,200m/40,026ft). The MiGs' radar warning receiver often sensed that the aircraft was being 'painted' by enemy radars but no missile warning ensued. On discovering a Hawk launcher the pilot would simply switch on the 'Siren' ECM set and carry on with his business. Deep penetration flights continued into October 1972. The Israeli ambassador to the United Nations lodged a formal complaint after each occurrence but no action on this issue was ever taken by the UN. The Israelisdidhave a reason to be nervous. Among the support equipment and other para- phernalia Det 63 had brought with them were bomb racks for the two strike capable 'RBs and FAB-500M-62T low drag bombs, specially developed for supersonic bombing. Each air- craft could carry up to eight such weapons; after being released at high altitude they could sail through the air for miles and miles. Howev- er, the Soviet pilots' missions did not include bombing. As an excuse for their inability to intercept the elusive MiGs the Israeli air defences stated that 'the object was clocked at Mach 3.2'! However, the flight recorders of the MiGs showed there were no major deviations from the prescribed flight profile. The aircraft were notalwaysflown by the book. On one occasion Bezhevets exceeded the 'red line' to get away from pursu- ing Phantoms; the flight recorder showed that the Mach limit had been more than tripled(l). Other sources state that it was WS pilot Krasnogorskiy who should walk away with the record (and get the 'speeding ticket'), as he reached 3,400km/h (2,125mph) in one of the sorties. This was dangerous because the air- frame could be damaged by overheating, but careful inspection of the aircraft showed no apparent damage. Still, the pilots received an unambiguous 'debriefing' afterthis incident. The new MiGs had a good reliability record, with very few failures despite the fact that the aircraft still had its share of bugs. Each aircraft came complete with a double set of spares - just in case. Nasty surprises did happen. On one occasion Stogov's aircraft suffered an engine flame-out and began decelerating rapidly, forcing the pilot to radio for help. He was ordered to return to base immediately or land at the reserve airfield from which escort fighters scrambled. In a few seconds, the engine revived spontaneously and Stogov pro- ceeded with the mission as planned. The trou- ble was traced to a faulty fuel flow control unit which the electronic engine control system somehow managed to correct. A more serious incident happened to Bezhevets. A main gear locking arm failed on the first aircraft reassembled in Egypt and the strut would not lock in the 'down' position. Bezhevets decided to land on the nosewheel and the locked mainwheel. Touching down at 290km/h (181 mph), he kept the aircraft's weight off the damaged strut as long as possi- ble. Finally the strut collapsed and the aircraft slewed, coming to rest on two struts and a wingtip. The landing was made so skilfully that the aircraft suffered only superficial damage to the wingtip and was soon flying again after repairs on site. (Other sources claim that the aircraft was returned to the USSR for repairs and a substitute MiG-25R sent in.) ------------------------------------------------------------------------------ -- Regards, Venik Visit my site: http://www.aeronautics.ru If you need to e-mail me, please use the following subject line: ?Subject=Newsgr0ups_resp0 nse |
#3
|
|||
|
|||
On Fri, 20 Aug 2004 01:31:17 -0400, Venik wrote:
Vello Kala wrote: Aircraft Speed Altitude Mach Number SR-71 Blackbird 2,275 mph (3,660 km/h) 80,000 ft (24,385 m) Mach 3.35 MiG-25 2,110 mph (3,390 km/h) 42,650 ft (13,000 m) Mach 3.2 This data is from Aerospaceweb. Question: SR-71 looks like alien plane, have very special design (incl tanks what start to keep fuel on flight only)etc etc. Mig-25 looks as pretty usual plane. But difference in speeds is relative minor, expecially if to look at what altitude it is reached. How it is possible? Do anybody have more data? Say, about SR-71 performance at 40 000 feet? I don't think that comparing MiG-25 to SR-71 is entirely inappropriate, considering that the Blackbird was one of MiG-25's primary targets and both aircraft were designed for high-speed, high-altitude recon roles. MiG-25 was designed as an interceptor and in this role it has outstanding performance. MiG-25 can be compared to SR-71 in terms of performance needed to intercept the Blackbird. MiG-25 certainly had the right performance for that. MiG-25 was also designed as a recon plane and in this role it can also be directly compared to the SR-71. And some comments about the comments in this thread. MiG-25 is not made of stainless steel but of nickel steel alloy similar in composition to the nickel alloy used for X-15. The Valkyrie, on the other hand, was made of predominantly stainless steel. Operational requirements for MiG-25 differed drastically from those of SR-71. MiG-25 was designed to operate as any other Soviet fighter aircraft without any specialized facilities. This was also a factor in the choice of airframe design and construction materials. Nickel steel alloy used in MiG-25 construction does not carry a strength penalty when compared to titanium. MiG-25 was build to have an exceptionally strong airframe. One must not forget that MiG-25 had to meet a substantially higher level of airframe stress requirements than SR-71. MiG-25 was a mass-produced combat aircraft (a total of 1,186 were manufactured), while the total production run of the entire A-12/YF-12/SR-71 line was only 49 aircraft or so. And this would explain the fact that the Mig-25 never managed to intercept an SR how? The Mig simply could not catch an SR-71, and probably could not even track it. The SR-71 succeeded, the Mig failed. Al Minyard |
#4
|
|||
|
|||
Alan Minyard wrote:
And this would explain the fact that the Mig-25 never managed to intercept an SR how? The Mig simply could not catch an SR-71, and probably could not even track it. The SR-71 succeeded, the Mig failed. I think you are mistaking an interceptor for a race car. You see, it does not need to exceed or even to match the speed of its target to complete an intercept. MiG-25's main drawback was its missiles. Other than that, the MiG-31 was succesfull in retiring the SR-71. -- Regards, Venik Visit my site: http://www.aeronautics.ru If you need to e-mail me, please use the following subject line: ?Subject=Newsgr0ups_resp0 nse |
#5
|
|||
|
|||
|
#6
|
|||
|
|||
On Sat, 21 Aug 2004 15:14:17 -0400, Venik wrote:
Alan Minyard wrote: And this would explain the fact that the Mig-25 never managed to intercept an SR how? The Mig simply could not catch an SR-71, and probably could not even track it. The SR-71 succeeded, the Mig failed. I think you are mistaking an interceptor for a race car. You see, it does not need to exceed or even to match the speed of its target to complete an intercept. MiG-25's main drawback was its missiles. Other than that, the MiG-31 was succesfull in retiring the SR-71. The SA-5 had a better chance of downing a Blackbird than the Mig-31 and that didn't seem to stop them. |
#7
|
|||
|
|||
Scott Ferrin wrote:
The SA-5 had a better chance of downing a Blackbird than the Mig-31 and that didn't seem to stop them. Remind me: what is the current operational status of the SR-71? -- Regards, Venik Visit my site: http://www.aeronautics.ru If you need to e-mail me, please use the following subject line: ?Subject=Newsgr0ups_resp0 nse |
#8
|
|||
|
|||
Venik!!!! Good to see you again. Heaven knows I hardly ever agree with you..
(I think you stated that the sky was blue one time and I had to run outside to make sure) but you are always entertaining. "Venik" wrote in message ... Alan Minyard wrote: And this would explain the fact that the Mig-25 never managed to intercept an SR how? The Mig simply could not catch an SR-71, and probably could not even track it. The SR-71 succeeded, the Mig failed. I think you are mistaking an interceptor for a race car. You see, it does not need to exceed or even to match the speed of its target to complete an intercept. MiG-25's main drawback was its missiles. Other than that, the MiG-31 was succesfull in retiring the SR-71. -- Regards, Venik Visit my site: http://www.aeronautics.ru If you need to e-mail me, please use the following subject line: ?Subject=Newsgr0ups_resp0 nse |
#9
|
|||
|
|||
On Sat, 21 Aug 2004 15:14:17 -0400, Venik wrote:
Alan Minyard wrote: And this would explain the fact that the Mig-25 never managed to intercept an SR how? The Mig simply could not catch an SR-71, and probably could not even track it. The SR-71 succeeded, the Mig failed. I think you are mistaking an interceptor for a race car. You see, it does not need to exceed or even to match the speed of its target to complete an intercept. MiG-25's main drawback was its missiles. Other than that, the MiG-31 was succesfull in retiring the SR-71. I guess it would just need to get close enough to fire a missile at it. At least that's the concept of "interceptor" as I understand it, it's not a dogfighter... -- __________ ____---____ Marco Antonio Checa Funcke \_________D /-/---_----' Santiago de Surco, Lima, Peru _H__/_/ http://machf.tripod.com '-_____|( remove the "no_me_j." and ".sons.of" parts before replying |
#10
|
|||
|
|||
I would suggest you talk with several SR-71drivers concerning whether they
would knowingly fly into a "Mig-25 infested" area with the Mig-25 drivers knowing he was there. The answer is and would be a resounding NO! And why, because the Mig-25 would have a reasonable chance of blowing his butt right out of the sky. Just because it never happened doesn't mean it can't. Keep in mind, to the best of my knowledge, all Mig-25/SR-71 encounters occurred off shore, not a direct invasion of Soviet airspace (different rules there gentlemen). Put a SR over Moscow and watch what happens. I suspect little pieces of titanium would be littering the countryside. A good comparison is the F-15 vs Mig-25. The F-15 could not tail chase the Mig-25 on its best day, as the Mig-25 could not tail chase a SR. The delta speed differences are about the same between the two comparison. But yet, the Israels dropped two Mig-25s with F-15s. The reasons are simple, and it has nothing to do with speed. The answer lies within proper tactics and tracking/firecontrol systems. The point being made is that there are no winners and losers with the Mig-25 and SR. The Mig-25 and SR served their missions well. The 25 kept western world aircraft out of their airspace, and the SR performed recce missions that simply could not have been done with other aircraft. As far as the SR retiring, the Mig-31 had very little, it not nothing to do with it. That was simply the cost of operations coupled with new capability. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Blackbird books (was: hi-speed ejections) | Paul A. Suhler | Military Aviation | 0 | February 5th 04 03:39 PM |
Victor Belenko's Narrative of Blackbird Activity in Soviet Far East | frank wight | Military Aviation | 3 | January 8th 04 12:07 AM |
Refuting blackbird folklore | frank wight | Military Aviation | 42 | December 3rd 03 09:24 AM |
SR- 71/ Blackbird lore | Larry Dighera | Military Aviation | 28 | July 31st 03 02:20 PM |
Blackbird lore | Air Force Jayhawk | Military Aviation | 3 | July 26th 03 02:03 AM |