6 ms·

Mentions Have Blue, but does not include a picture. See it here [0]. Certainly one of the most ungainly-looking aircraft. Eventually led to the F-117A Nighth

by hcrisp 4y ago

Mentions Have Blue, but does not include a picture. See it here [0]. Certainly one of the most ungainly-looking aircraft. Eventually led to the F-117A Nighthawk, nicknamed the "Wobblin' Goblin" due to handling characteristics which required computer control to keep it stable. [0] https://en.m.wikipedia.org/wiki/Lockheed_Have_Blue https://en.m.wikipedia.org/wiki/Lockheed_Have_Blue

gonzo41 4y ago
I loved this aircraft as a boy. It just screamed future.
whalesalad 4y ago
A lot of old timers still call the F117 Have Blue from time to time. My grandfather worked on that program at Lockheed in Burbank/Palmdale.
- runjake 4y ago
  Have Blue and the F-117A are not the same aircraft and they are substantially different planes. Have Blue is considerably smaller than the F-117A and has a different body design. Most civilians don’t know this but it’s worth Googling and comparing the two aircraft side by side.
  - runjake 4y ago
    I'm not sure why the massive downvotes. The above is fact. They are substantially different aircraft, although similar in appearance at a quick glance. HAVE BLUE is a much-smaller, differently-shaped demonstrator that was a predecessor to SENIOR TREND, which is what the F-117A actually came from (Wikipedia is inaccurate here).
brightball 4y ago
If you haven't read Skunk Works, you definitely should. Covers a lot of Lockheed history including the development of the F-117, SR-71 and U2. Really fantastic read.
Steve44 4y ago
> which required computer control to keep it stable. I think most modern fighters are like than. The fly-by-wire isn't just an electronic control as with early developments, but basically tells the computer what you want to do and the computer then drives the control sequence to do what you ask. https://www.eurofighter.com/advantages https://www.eurofighter.com/advantages > Eurofighter Typhoon has a foreplane delta design, which is inherently – and intentionally –aerodynamically unstable in subsonic flight. This was developed with experienced pilots to provide enhanced manoeuvrability while still being highly intuitive to fly. > The instability in subsonic flight requires a complex flight control system to support the pilot as the computer systems can react more quickly at lower speeds. When Eurofighter Typhoon crosses into supersonic flight, the point of instability moves behind the centre of gravity, giving a stable aircraft for high performance flight. > The advantages of an intentionally unstable design include greater agility at subsonic speeds as well as reduced drag and an overall increase in lift for enhanced short takeoff and landing (STOL) performance. Proposed engine enhancements such as vectored thrust will further boost the agility of the aircraft.
- eduction 4y ago
  Correct. The F-16, dating to the mid 1970s, was the pioneer here and was incredibly maneuverable as a result (certainly for its era but probably for today as well).
syntaxing 4y ago
Most control system of fighter jets (if not all?) in US operation are designed to be unstable in the Nyquist plot to begin with (layman terms, designed to be unstable like balancing a triangle on its tip). Downside is that your need special on board computers to always actively push the aircraft back into the stable region. Upside is that you maximize frequency response (whatever that means in the block diagram).

by hcrisp 4y ago

gonzo41 4y ago

I loved this aircraft as a boy. It just screamed future.

whalesalad 4y ago

A lot of old timers still call the F117 Have Blue from time to time. My grandfather worked on that program at Lockheed in Burbank/Palmdale.

runjake 4y ago
Have Blue and the F-117A are not the same aircraft and they are substantially different planes. Have Blue is considerably smaller than the F-117A and has a different body design. Most civilians don’t know this but it’s worth Googling and comparing the two aircraft side by side.
- runjake 4y ago
  I'm not sure why the massive downvotes. The above is fact. They are substantially different aircraft, although similar in appearance at a quick glance. HAVE BLUE is a much-smaller, differently-shaped demonstrator that was a predecessor to SENIOR TREND, which is what the F-117A actually came from (Wikipedia is inaccurate here).

brightball 4y ago

If you haven't read Skunk Works, you definitely should. Covers a lot of Lockheed history including the development of the F-117, SR-71 and U2. Really fantastic read.

Steve44 4y ago

> which required computer control to keep it stable. I think most modern fighters are like than. The fly-by-wire isn't just an electronic control as with early developments, but basically tells the computer what you want to do and the computer then drives the control sequence to do what you ask. https://www.eurofighter.com/advantages https://www.eurofighter.com/advantages > Eurofighter Typhoon has a foreplane delta design, which is inherently – and intentionally –aerodynamically unstable in subsonic flight. This was developed with experienced pilots to provide enhanced manoeuvrability while still being highly intuitive to fly. > The instability in subsonic flight requires a complex flight control system to support the pilot as the computer systems can react more quickly at lower speeds. When Eurofighter Typhoon crosses into supersonic flight, the point of instability moves behind the centre of gravity, giving a stable aircraft for high performance flight. > The advantages of an intentionally unstable design include greater agility at subsonic speeds as well as reduced drag and an overall increase in lift for enhanced short takeoff and landing (STOL) performance. Proposed engine enhancements such as vectored thrust will further boost the agility of the aircraft.

eduction 4y ago
Correct. The F-16, dating to the mid 1970s, was the pioneer here and was incredibly maneuverable as a result (certainly for its era but probably for today as well).

syntaxing 4y ago

Most control system of fighter jets (if not all?) in US operation are designed to be unstable in the Nyquist plot to begin with (layman terms, designed to be unstable like balancing a triangle on its tip). Downside is that your need special on board computers to always actively push the aircraft back into the stable region. Upside is that you maximize frequency response (whatever that means in the block diagram).