Lockheed F-117 Nighthawk
Source : https://www.defense.gov/
1. Introduction :
Lockheed F-117 was a USAF operational stealth ground attack aircraft, used to destroy ground targets and built to avoid radar detection with the design to deflect all radar signature away from the transmitter. The flat and faceted surface designs are what makes this plane stealthy, making this plane has a very small Radar Cross Section (RCS) compared to other non stealth aircraft. Now what is Stealth and RCS? Stealth or Low Observable (LO) aircraft is an aircraft technology built to avoid reflecting radar signature back to the transmitter ideally to fully avoid detection by radar, therefore it can launch an attack without getting detected by radar. In reality the aircraft still can be spotted by eyes but undetected by radar or sometimes can not be fully undetected because of several other factors (opening weapon bay, drag that produces friction and heat, etc). Radar Cross Section is a measure of aircraft ability to reflect radar signature back to the transmitter. The higher number of RCS means the more radar wave reflected back to the transmitter and likely to be detected by radar. F-117 has a very small number of RCS thanks to the radar deflective design. It deflects most of the radar wave away from the transmitter, only a few of them back to the transmitter, therefore it still appears, but so small on the radar so that it's negligible like clouds. Here is the list of physical size of aircraft compared to RCS.
As you can see, F-117A Nighthawk, B-2 Spirit, and B-1B Lancer have very small RCS and appear less than 1m2 on radar. That's because these are stealth aircraft. No matter how big the aircraft as long as the design is deflective, it is likely to be undetected by radar. B-52 Stratofortress is a heavy bomber with a big size and doesn't have any stealth characteristic, therefore it appears really big on the radar and of course it will be detected easily.
2. History
The development started in 1975, when Lockheed Skunk Works/Advanced Development Project initiated a top secret stealth aircraft development. After the development, the first delivery was delivered to USAF in 1982. It was nicknamed the "Stink Bug" and "Bat Plane" just because of its physical appearance. The plane was considered successful and effective during the Gulf War in 1991 because of its accurate night bombing mission and still remain undetected by radar.
The first and only aircraft was shot down in 1999 during NATO Bombing of Yugoslavia (Operation Noble Anvil) in Serbia by Yugoslavian Army. The aircraft was proven ineffective against obsolete long wavelength radar that was used by Yugoslavian Army led by Col. Zoltan Dani to shoot the aircraft down. It's stealth ability only effective against modern short wavelength radar. The aircraft, Lt. Col. Dale Zelko's F-117A was even already detected from the ground 31-37 miles away. Until now, one of the problem of stealth aircraft as I mentioned above is the significant increase of RCS number by opening weapon bay making the stealth ability disappear, and that's when the ground crew successfully locked on Dale Zelko's F-117A with S-125 missile, just because he was opening the weapon bay and was ready to release the bomb. Well, he evaded the first missile, but unfortunately the second one hit him. His aircraft was badly damaged but still able to bail out safely. He landed in a village in the south of the town Ruma, Serbia. He immediately hid himself by smearing mud on his face so the locals, dogs, police couldn't recognize him. Eight hours later, he was rescued by a helicopter. The most interesting part was after the war ended, in 2009 one of Zoltan Dani's son found Dale Zelko on the internet and contacted Zelko to have a meeting with his father. In 2011 Dale Zelko flew to Serbia and met the man who shot him down. Zoltan Dani had given up shooting planes and has become a baker. The two has become friends since then.
The Canopy of Dale Zelko's F-117A
The aircraft was retired from USAF in 2008, but even though it has been decommissioned. The aircraft is a recallable storage, meaning that somehow if necessary the aircraft can be commissioned again to another bombing mission. Even some of them still fly in 2016.
3. Airframe Design and Structure
The aircraft's airframe is covered with radar-absorbent material. There is a lot of radar-absorbent material types. The one that F-117A has absorbs radar wave and convert it into heat then dissipated, thus the radar wave doesn't come back to the transmitter. The exhaust was designed with fine mesh to reduce heat signature that might provide the enemy to track the aircraft. It couldn't use radar to avoid giving position to the enemy and it relies on passive infra red camera on the nose. Keeping the airframe flat and facet are important stealth characteristics, so the fuel tank and bombload are kept inside (specifically bombs are inside the bomb bay). When the bombs are about to be dropped the weapon bay opened, then the bombs are dropped, and finally the weapon bay closed again immediately to maintain stealth. This is a subsonic aircraft, instead of supersonic therefore it doesn't go as fast as the speed of sound or Mach 1 (Mach 1 = 1234.8 Km/h). Which means it was slow on today's standard so that was why F-117 only attacked by night. Also, the cockpit view was very limited to see outside. Since it was night, the cockpit view was limited, and they couldn't see outside. F-117A pilots didn't see outside to aim the bomb. They relied on the data shown on Multi Function Display (MFD) provided by the infra-red camera on the aircraft. They just followed the instruments on the cockpit to do the mission. Even the bombs were laser guided and it was extremely accurate.
Exhaust Mesh Painted in Silver (Picture is Mine)
MFD of F-117 Cockpit
Source : AVSIM
Infra Red Nose Camera Below The Front Window (Picture is Mine)
4. Aircraft Code
USAF aircraft code usually have abbreviation, for example the code "F" (like F-16) stands for Fighter role, "A" (like A-10) stands for attacker role, "F/A" (like F/A-18) for both Fighter & Attacker role (Multirole), "B" for Bomber role, etc. The F-117A is an exception because it has the strange aircraft code, was named "F" that stands for Fighter but the aircraft itself is not a Fighter, but an Attacker. It doesn't have any guns nor does air to air missile. It only carry bombs or air to surface missiles.
5. Aircraft Specification (F-117A) data from the book and internet :
- Engine : 2 x 4900kg (10,800 lbs) thrust General Electric F404-GE-F1D2 non-afterburning turbofan
- Wingspan : 13.2 m (43ft 4in)
- Length : 20.1 m (66ft)
- Weight : 23,814kg (52,500lb)
- Top Speed : 993 Km/h
- Armaments : 2 x internal weapon (one hardpoint each), total of 2 weapons with option of laser guided bombs or nuclear bombs or AGM-65 Maverick air to surface missile or AGM-88 High speed Anti Radiation Missile (HARM) air to surface missile.
That's all for this short and first article of this blog. Some of this content are the summary using my own words from the book and some are from my own knowledge. The book is cited below and as a quick review, the book is good to read and has a lot of information but it still has some mistakes that I have to recheck on the internet. I hope you can enjoy and gain more knowledge from here. Also, I'm open for correction or opinion, just comment on the comment section below. See ya.
Source :
Grant, R.G. 2017. Flight The Complete History of Aviation. London : Dorling Kindersley Limited.
https://www.warhistoryonline.com/history/that-day-the-serbs-did-the-impossible-shot-down-an-f-117-nighthawk.html
https://www.airforce-technology.com/projects/f117/
https://en.wikipedia.org/wiki/Lockheed_F-117_Nighthawk
Yooo :v
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