If you look at the manual that came with the E-flite F-16 Falcon 80mm EDF Jet, you might find a section in it for enabling reverse thrust. My manual has it, and since the feature is disabled from the factory, it seems like a neat capability to have. You can use it when taxiing as well as for braking after landing on a smooth surface, to reduce your landing rollout. There is at least one YouTube video online that talks about reverse thrust on this aircraft while also stating it’s not mentioned in the manual or anywhere else, but can still be enabled. Either way, it is doable if you have a spare channel and switch on your transmitter for it.
There are two ways to enable reverse thrust on the ESC (Electronic Speed Controller): one is to use a compatible transmitter to enable it through the aircraft’s receiver, and the other is to use a Smart Programmer Box (SPMXCA200), which is about $30 USD. Since I have an older transmitter at the moment which doesn’t have the needed capabilities for programming an Avian Smart ESC, I decided to just purchase the Smart Programmer Box online. I specifically have the V2 version. It also has a LiPo battery tester, so it does serve an additional function.
However, as I went to use the Smart Programmer Box, I quickly ran into a confusing situation with the ESC, which is model SPMXAE1100A in my particular aircraft. The “A” variant is specifically for the E-flite F-16 Falcon 80mm EDF (EFL87850). Based on the wiring diagram for the Avian 100 Amp Brushless Smart ESC, there should be two cables coming out of it apart from all the main power leads: one for the throttle that goes into the receiver, and another for programming and possibly auxiliary power. Under the removed canopy of the aircraft, there are indeed two cables from the ESC, based on what I just described. I figured great, this will make it easy to access the programming capabilities of the ESC without having to get directly at the ESC, which is of course nestled further back in the fuselage and not immediately accessible in the same way the receiver and cables are.
Of the two cables coming out of the ESC and into the canopy opening, the throttle cable will not help with programming. The other cable is labeled “AUX BEC” and after it passes into the canopy opening, it splits into one connector with two power wires, and another connector with just the gray wire. I had assumed the gray wire was the programming wire. I plugged it into the ESC port of the Smart Programmer Box and then I plugged the AUX BEC power connector into the Box’s power port. The Box powered up, showed its firmware version, but after proceeding it would stay stuck at the ESC connecting stage. It turns out that gray wire isn’t for programming. Possibly it’s used for some future feature. Out of the box, it’s not connected to anything, but the power connector is connected into the receiver which should at least supply the receiver with a redundant power connection from the ESC. In my case, either the throttle or the auxiliary BEC connector will power the receiver.
On my particular ESC, the programming port is an unused port that you have to directly access at the ESC to plug into, using the wire supplied with the Smart Programmer Box. The ESC manual’s wiring diagram even states some ESCs vary in terms of the programming wiring or something to that effect. A YouTube video out there mentions needing to unplug a fan to use the programming port. My ESC does not have a fan. Life is messy and unpredictable!
So, here are the steps you actually have to do, if you have my setup and equipment. Yes, this is more involved that I initially thought, but after a lot of research online and talking to Horizon Hobby support, I figured this out on my own (although credit does go to support for helping me rule out other options).
- Remove the vertical stabilizer. The ESC is right under it and quite accessible. But in order to access the port, I needed more slack in the wires so I could pull the ESC partly out. For this, proceed to the next steps.
- Remove the engine cover on the bottom of the fuselage, which is held in place by two screws. This thing came off with a fight, but I eventually got it shimmied off.
- Remove the engine, which is held in place by four screws. You need to do this to give the three engine lead wires enough slack so you can pull the ESC out.
- Pull the ESC out of the vertical stabilizer hole enough to access the front facing side where the two wires that go into the canopy opening are coming out of.
- Now you should see the port you can plug your programming cable into. The Smart Programmer Box should now work and detect the ESC. At this point, you can follow the aircraft manual’s instructions to program the ESC with reverse thrust.
- Test reverse thrust carefully. Secure the engine and keep fingers away from blades. Then disconnect the Programmer Box from the ESC and put everything back together.
Ok, so that was a lot more work than I had initially thought, and the manuals are all either limited in detail or the details that are there aren’t accurate to product realities. But with perseverance, I now have reverse thrust on my F-16! It’s pretty neat. Just don’t flip the reverse thrust in flight. It’s for ground operations only. The manual also states this at least twice. At least it thoroughly covers that part, once you get the feature enabled.