The USAF Thunderbirds performed at a local airshow yesterday. I’ve seen them many times but this is the first time that I saw one of the jets with a large external center-line tank. Number 4 in the diamond formation, if that matters. Why would they fly like this? Maybe it wasn’t fuel but some other equipment? Cameras or something?
It’s purely there to aid the other pilots in distinguishing the two seat F-16D from the rest of the F-16Cs.
Source: I asked a member of the ground crew this exact question at RIAT last month.
- Can’t they distinguish it because it has like, ya know, an extra seat?
b) Why are they flying one oddball F-16D?
*) Miss you Opal.
If you are in formation slightly below and behind you would not be able to view the extra seat. I can’t speak to how important that would be. I guess it would depend on whether the extra seat gives slightly different flight characteristics which would be important to know in close maneuvering. If that is the case you would want an immediately obvious visual clue as to which style of jet you were next to.
I don’t know if they only have one F-16D or more. There are a few reasons that they could want a couple of 2 seaters. The ability to fly support crew around with the planes or the ability to take press or other riders for ride alongs would both be reasons. Canada’s Snowbirds team takes advantage of the 2 seater Tutor jets for both purposes.
This is the reason. They are not always looking at the D model from a position where the second seat is visible.
At RIAT they used the two-seater to give the lead singer from McFly a ride during the display. I was surprised to find out that he is a qualified pilot, and apparently they pulled 9.6g with him. Impressive.
I met a few of the pilots during Sunday night’s Hangar party, and they are thoroughly nice guys.
Why do they need to know which one is the F-16D?
It’s not about ID’ing the plane although it is handy. When you install a second seat-stick actuator you have to remove a fuel tank to accommodate them; ergo, you need to carry more fuel somewhere else that the singles have inboard. The F-18 A/D is the same way.
20 year Avionics Tech with the RCAF, in case you wondered why I would know this… 
Yeah, but it’s not like the BAs are flying long-range strike missions. The rear fuselage and wing tanks should be more than enough for an airshow.
Normally we will put around 6000 litres of fuel in an F-16 after it displays. This is true for the US, the Belgians, the Turkish, the Dutch, with or without conformal fuel tanks, so the fuel tank slung underneath is not carrying fuel. The thunderbirds don’t always fly all together. They separate out into two groups. Nothing wrong with knowing where the passenger is.
They do have to fly the planes from show to show though (I would assume that is how they travel). That would necessitate the additional fuel tank on the two seater.
Sure, but you don’t carry enough fuel to ferry a plane during an airshow. That just means you get the biggest possible explosion in the event of an accident.
It might have something to do with the safety factors of attaching and removing the tank every time they move locations vs the additional danger of leaving it attached during the show but I’m just guessing so I’ll bow out until an expert chimes in.
I’m not an expert by any means, but I do volunteer at RIAT (Royal International Air Tattoo), and I work on the refuelling team. I refuel lots of planes from lots of different countries, including lots of F-16s. I will admit that as a volunteer, I’m not allowed to refuel anything from the USA. There is some contractual loophole that precludes volunteers from fuelling US aircraft and it is left to on-site contractors. That being said, we work with those same contractors, and when at RIAT, US aircraft get fuel from the same place and the same trucks at RAF Fairford that we use. I had the pleasure last year of refuelling a USMC F-35B, so it does happen.
I can tell you that when I asked the Thunderbirds ground crew if the drop tank on the D model needed fuel (standard question for display teams on the Monday departure day - topping off drop tanks is pretty much all we do for the long distance teams), they told me it was only there for ID purposes.
They all flew back to the US together and refuelled in the air together.
Aren’t their routines so well rehearsed that they know where everyone else is at all times? And why aren’t there markings on the single seaters? Wouldn’t mistaking one single seater for another be just as bad as mistaking the 2 seater for a single?
Could they have meant that it was to help people in the crowd to ID the 2 seater?
Sorry, I’m not doubting you, but I’m not understanding why that particular plane needs to be identified.
It’s at the center of the formation, so it’s an easy way to orient oneself. Same reason your keyboard has tabs on F and J, but not the other letters.
This is circular and we aren’t any closer to the real reason why the Thunderbird’s F-16D carries a center line fuel tank than when we started.
Thunderbird 4 was already kinda identifiable (at least late season) because itsvertical stabilizer would be stained blackfrom the jet exhaust of the rest of the aircraft in the diamond.
I remember the F-4 Phantom II Thunderbirds back in the early 70s; the J79 engines kicked out a soot trail that you could walk on. With the more modern high-bypass turbofans, it takes a while for the slot Thunderbird to get a dirty tail, and they don’t always allow it nowadays (washing it clean rather than allowing it to accumulate). But it was a distinctive thing, and a pretty good way to tell #4 from he the rest of the diamond team.
ETA: Back to OP’s question, I have NEVER seen any Thunderbird, Blue Angel, or any other military aerobatic demonstration team performing with anything other than a perfectly slick conformation: no pylons, no tanks, nothing whatsoever on the hardpoints. And I couldn’t imagine any valid reason why. “Identify #4”? Silly on the face of it. #4 is in the slot position, and the presence of a two-person cockpit with elongated canopy is more than enough to distinguish it. Every pilot knows their position relative to #1, which is the only plane they need to identify anyway, because it localizes the formation. Everyone elese forms up off of the lead bird.
If “distinguishing” an airplane in the formation actually mattered, they’d put the tank on #1.
So when the D model isn’t being used, they just fly around lost?
Also, if you are having trouble distinguishing which airplane is which while in formation, maybe you shouldn’t be a Thunderbird pilot.
Former F-16A & B driver in a world now long long ago and far far away…
Some facts:
The single seat C model has X amount of internal fuel tankage. The 2-seat D model has ~25% less. The external centerline fuel tank makes up for that capacity difference less a bit. The centerline tank adds some drag, but less than you might think; the complicated shape is pretty carefully chosen versus to local flow field under the fuselage. With the result that the ferry range or endurance of a C with no external tanks and a D with a centerline tank are pretty similar. Although the external tanks are ground removable and inflight jettisonable, the process to remove or install one takes a bunch of man-hours and involves a bunch of specialized tools, support carts, test equipment, etc. My combat unit tended to install them on one subset of our airplanes and just leave them on there for weeks and months. In the A model with full internal fuel we could normally fly a 1-hour air-to-air practice mission at middle altitudes comfortably, but 1 hour plus 12 minutes was getting antsy on fuel and you’d definitely run out before 1 hour 30 minutes. But … If you took off in full afterburner and just left the throttle there at low altitude, that ~90 minutes of fuel would be entirely spent in just 8 minutes. :eek:.
My conjecture:
It’s much easier to plan and fly a ferry mission from one airshow to the next when all the aircraft in the formation have about the same range. Likewise, because an airshow is flown mostly at very high power settings, pretty much a full load of internal fuel is needed to fly the standard show including having some contingency fuel for somebody having a problem that precludes landing immediately after as planned. The D model with no external tank would be hard-pressed to fly the show with enough (any?) contingency fuel left at the end. Removing the tank and reinstalling it would introduce unreliability, increase man-hours, increase the amount of support gear they need to transport, and generally be a PITA for no real gain. So it isn’t done.