The advantage that Stealth technology has bestowed on those countries which use it is hard to underestimate and it has changed the way warfare is conducted but it’s not just aircraft which use it, ships, vehicles even troops can use varying types of technology help hide from detection, this is how stealth has changed modern warfare.
Ever since it was discovered that objects like planes or ships could be detected by reflected radio waves, which developed into the radar systems of today, there has a concerted effort to try and keep them hidden.
The theory behind stealth aircraft is that a smaller number can carry out surprise attacks behind enemy lines giving little or no warning or time for the enemy to react and still have the same destructive impact as a larger non-stealth formation whilst having a much greater chance of survivability.
To do this they need to remain as undetectable as possible for as long as possible, the goal being to stack as many of the odds of success in your favour.
But it wasn’t always like that, during the Vietnam war, Russian made radar-guided surface to air missiles caused a big problem for the US airforce requiring dedicated aircraft to take on the air defence systems as part of many strike missions. In the Yom Kippur War, the Isrealis lost a significant amount of aircraft again because of radar guided surface to air missiles.
In a non-stealth attack deep behind enemy lines, a typical formation might consist of nine aircraft including four F-16CJs with eight AGM-88 HARM High-speed Anti-Radiation Missiles that home in on radar transmissions to take out the surface to air missiles batteries. Then a B1-B bomber with four JDAM precision-guided bombs to destroy buildings or other high-value targets and another four F-16CJs with eight AIM-120 advanced medium-range air to air missiles for defence against enemy fighters.
So what about doing this with stealth aircraft. Well if its primarily a bombing mission against buildings then a single B-2 stealth bomber or two F-22’s or two F-35’s could in theory fly around Surface to Air missile and radar sites thus removing the need to have dedicated Suppression of Enemy Air Defense aircraft and missiles. As they are most likely not to be detected by air defence fighters, that’s there is no need of the for the air to air missiles and the aircraft carrying them either, so this leaves just the four JDAM bombs and the aircraft to carry those.
Now that is just the theory and in real life there might be more aircraft involved like refuelling tankers, radar jamming and coordination aircraft depending on the mission and where it is. But you can see there is a large reduction in the number aircraft and armaments to do the same mission and with an increased likelihood of the planes and crews making back OK.
Losing aircraft to over enemy territory not only risks the death of the pilots but also highly classified technology falling into enemy hands. If the crew survive then there could a hostage situation and all the bad PR that comes with It, like Gary Powers U-2 spy plane which was shot down over Russia in 1960 and pilots shot down over Vietnam and in other conflicts.
The US was the first to have true stealth aircraft in active duties with the F-117 Nighthawk from 1988 and the B-2 Stealth Bomber from 1997, these being the only stealth aircraft that have seen combat until more recently when the F-22 and F-35 saw action in the Middle East.
The F-117 was used in the invasion of Panama, the war in Yugoslavia and the first and second gulf wars and is the only stealth aircraft to be lost due to enemy fire.
This brings on to the issue the stealth is not 100% effective, it doesn’t make an aircraft invisible or undetectable but it greatly reduces the ability of an enemy to see it until its much closer than a normal aircraft might be.
To give you an idea of the difference between the F-15, a fourth-generation aircraft designed in the 70’s and a current fifth-generation F-35. The F-15 has a radar cross-section about 5000 times larger than that of the F-35. The F-22 raptor has an even smaller radar cross-section and better infra-red masking with the vectored rectangular exhausts compared to the F-35’s round ones.
Although giving a definitive radar cross-section is incredibly difficult because it changes depending on size, material, shape and angle it measured at as well as the frequency of the radar, but as a rough guide most centimetre radars would see the F-35 was a similar size to a metal golfball and the F-22 similar to a metal marble.
As far Bombers go, the B-2 Stealth bomber has the Radar Cross Section about the size of a football and a B-52 for comparison is about the size of a barn. The B-2 is now 30-year-old tech and the new version, the B-21 will bring it upto date and inline with modern designs so even for its size expect it to be the golfball range or less.
Stealth aircraft can be seen by targeting radar but only when they are very close usually less about 10km. Other radar systems which use low-frequency VHF, passive and multistatic radar can also pick them up at greater distances but these methods are too low resolution to get target fix but will give an indication something is coming and where it is within a few hundred meters.
Stealth missions have to be carefully planned to make to most of the technology and even the way the aircraft is flown can make a difference.
Part of the reason why the F-35 uses the advanced helmet system in conjunction with the onboard radar and distributed aperture system cameras which allows the pilot to effectively see through the body of the aircraft is so that he or she doesn’t have to move the aircraft to see what’s around him or on the ground.
Moving or banking the aircraft when its approaching air defences increases the likely hood of it being picked up by the computers analysing the radar signal returns, keeping the aircraft in level stable flight lets it blend into the background noise and not stand out as a moving object.
A major part of most conflicts is SEAD or Suppression of Enemy Air Defences, a task normally done by non-stealthy 4th generation aircraft. One plane acts as bait for the radar and others to target the radar once it switched to targeting mode.
Aircraft like the F-22 and F-35 can fly behind enemy lines using its sensor fusion to build up a map of where the radar and missiles threats are and pass the terminal guidance to other dedicated 4th gen aircraft which can launch missiles from a safe distance
This type of suppression and destruction of enemy air defences is called “rollback” and has been successful in all the modern conflicts to convert “contested” airspace into “uncontested” airspace and was done by wild Weasels, aircraft equipped with anti-radiation missiles. With the stealth capabilities of the F-35, it’s touted at the ultimate Wild Weasel, the only problem is that in order to remain to stealthy it can’t use wing-mounted weapons and thus is limited to its internal weapon storage.
The method of detecting and flying around missile and radar sites was used extensively by the F-117s in the Gulf wars and Yugoslavia but in wartime, things can and do go wrong.
The only stealth aircraft so far to be shot down by a surface to air missile was an F-117 on March 27th 1999 over Serbia. The F-117 was the first stealth aircraft to be developed and compared to later designs like the F-22 and F-35 is not as stealthy.
The way it was brought down was more down to the ingenuity of the commander of the missile battery Colonel Zoltán Dani, Serbian intelligence and NATO mistakes as it was any deficiency in the stealth design.
On the night of the mission, missile commander Dani knew from spies that the EA-6 Prowler electronic radar jammers and “wild weasel” anti-missile aircraft which would have accompanied the F-117s were grounded due to bad weather so they would be flying alone in the dark.
The Serbs had also cracked the NATO communications between US fighters and the Airbourne radar planes directing them. Using this they could piece together the routes used by the F-117s flying back to Italy from Yugoslavia.
NATO had a lot of radar jamming assets to the north so Dani set his radar pointing away from that area and only used the high frequency targeting sweeps in short 20 second bursts before moving to another location to avoid being detected and hit by NATO anti-radar aircraft.
Dani used his P-18 long-range acquisition radar on it’s lowest possible meter wavelength setting so that it would reflect off the interior of the aircraft and not be affected by the stealth skin. This setting was lower than the radar detectors on NATO aircraft were calibrated to detect, if these had been working on the F-117s they could have detected the VHF radar and moved away.
Dani picked up the four F-117s about 25km away. Knowing that they couldn’t counter-attack he used his the tracking data from the P-18 radar to aim the SA-3 targeting radar twice to try and get a lock but failed. As they flew by he tried again and this time was successful and got a target lock when they were 13km away and at an altitude of 8km or 26,000ft.
This also appears to have happened at the same time when one of the F-117s had it bomb bay doors open and making it a much more obvious radar target.
Dani fired two S-125 radar guided missiles with proximity fuses, one flew close by but didn’t detonate, the other exploded near one of the F-117’s causing it to lose control and crash. The pilot Lt. Col. Dale Zelko ejected and was picked US special forces about 8 hours later.
The crashed F-117 was captured and parts of the stealth airframe were believed to made their way to Russia and China for examination to help their stealth programs even though the technology by then was 20 years old.
About a month later another F-117 was damaged by a missile but was still able to fly back to base, though it’s believed that it was later removed from service.
Although this was an embarrassing loss for the US and has been used by many opponents to stealth programs to show that stealth aircraft could shot down by old Soviet Era radar and missiles, it also showed that a lot of elements had to come together in the right place at the right time for it to happen.
Sloppiness by the NATO commanders in overestimating the stealth capabilities of the F-117, reusing known air routes and not recognising the Serbs low frequency radar was operating below NATO recognised frequencies were major contributing factors to the loss of the F-117.
This had the effect of increasing the development of stealth for newer aircraft to make them even more stealthy and improve the way operations are managed to avoid the mistakes that happened here and not just in the US the but also in Russia and China which now have their own stealth programs.
It also has increased the development of countermeasures with new advanced low-frequency acquisition radars to find and track them knowing that it could be done with a much more systematic integrated air defence systems approach rather than relying on exceptional commanders in the field.
The B-2 bombers conducted operations in the second gulf war and Afghanistan and flew halfway around the world directly from Airbases in the US to get at targets and none have acquired a target lock by any missiles.
This new cat and mouse game of stealth and counter stealth will play out for decades to come but stealth still offers great advantages over earlier none stealth designs and with new manufacturing techniques evolving they will bring stealth to most areas of the airforce, weapons design and is already being used by the Navy with stealth ships able to look like a fishing boat to enemy radar and better able to defeat anti-ship missiles.