Flite Test F-4 Maiden at Birmingham RC! 

This jet actually looks like it's reasonably calm to fly.

My dad worked on the F4 in the Airforce. I just got into the hobby flying. My first plane is a 500mm Volantec Cub. 4 channel.

Great job flying and troubleshooting. Brings back memories... Served in the Marine Corps and was attached to VMFA-542 for its first Vietnam tour - April-December 1965. And of course, at that time, the squadron was flying F4 Phantoms. Would love to see you finish your FT F-4 as a Marine Fighter Attack aircraft. PS. My YT comment logo that you see was our squadron patch. The "patch" was panted on the vertical stabilizer - both sides if I remember correctly. Also, our call letters were WH, Whiskey Hotel, but we affection referred to it as Whore House. 😊

Awesome F-4 and awesome flying site. Hello from California

Real F-4 has two aux air doors on bottom that are open anytime the gear is down. More for cooling than anything else. As a side note, squadron mate took off with a leaking external center-line fuel tank and the fuel was sucked in around the engines thru those doors and lit by the afterburners. They ended up ejecting.

technical term for them is 'sucker doors' ..lol. On the Harrier inlet for example, these are spring loaded and open on the ground at high power settings when you need maximum airflow for vertical takeoff and not enough direct airflow thru the engine with no forward motion. Differential air pressure and the calibrated spring force controls when they open and close. but your technical analysis was correct. low air pressure was forcing the doors to suck closed from air flow on the underside of the fuse as well as ram air going down the duct to the motors. typically in full size aircraft bypass doors are either mechanically controlled via springs and differential air pressure or thru electo-mechnical control with co-ordination with airspeed/AoA/EPR and other sensor inputs. Nice F-4, when you upgrade to 6s it will really move. Hope you get the launch dolly sorted. Another option we've used in the past is a bungee /catapult launch. There should be plans on the web for ideas on this method.

Love a good flight study and test. No matter how good the simulation reality in the air can reveal different problems. Engineering things!

Great videos and love the Phantom, she flies well. Looks like a great day and what a flying site too.

Great video Ben, love seeing the problems, discovery, and solutions being implemented. A true flite test engineer right here!

Blow in doors were common on early jets. The widely separated inlets are more likely introducing asymmetric flow during turns. Your “cheater holes” are very close together on centerline and are less likely to be asymmetric in my opinion 🧐. The Phantom is always a favorite of a lot of people. Lots of color schemes possible! Awesomeness!

Those auxiliary intakes are a cool feature! Nice job figuring out how to make the airflow work with 4S on-site

That F4 is a beautiful plane! Cool to see how you figured out the cheater doors. I bet that's a monster on 6s.

Too much fun with this one Ben. Learned a few things in the process. Great build and awesome flights!

The saying you were looking for would be: "Not for the faint of heart!"

The baddies in WW2 did that launch style with the Komet.👍👍

What a great build Ben, I'm glad that you sorted out the airflow issue.

Fantastic flying, Ben! 😃 That place looks sweet! Seems to be really fun! Anyway, stay safe there with your family! 🖖😊

looks sweet brother

The phantom is cool, obviously, but that foamboard (?) Stearman is fantastic. 👏👏👏👏

Really noticeable more air flow to the EDF's on take off after removing cheater doors, it didn't even dip down at all. You through a 6s battery in it , you will see significant change for the better. The Phantom has been one of my favorites

Sounds like an easy 3d printer grill easy fix!

"if a jet can even be a floater"... U-2 has entered the chat.

Another informative video; thank you Professor Harber😀 The fans need to breathe 👌 Great build !

Bungee cord / catapult launch!

Sweet! Maybe make a trolley on an RC car? You’d need a takeoff assistant to drive it, but it would be like a catapult launch

I might need to get one of these!

Awesome build 🔥

Would love to see it on 6S

Cool bird and good flying!

Great video and informative! Have mine built and ready to maiden, do you have a suggestion where the C.G. point is on this jet?

Working on a 6s build of this. It will be interesting to see how it goes with the more power. If I will need to cut off the doors or not.

Most of the old model jets like Bob Violet’s planes had screened over “cheater” holes. That would probably take care of the issue and you can paint them to match.

My airliner had two 70mm fans running on one 6 cell 5200 and flew amazingly well. Just sayin.

Try closing off those auxiliary inlets.

Naca ducts?

Crosswind doesn’t cause cross flow on an aircraft unless you intentionally hold a “crab angle” using rudder. I would hope you’re not holding rudder “into the wind” during a fast pass, even if there is a crosswind blowing. The aircraft doesn’t fly relative to the ground. It moves within the airflow and relative to that airflow. Consider that a headwind gives you airspeed on the ground but makes no difference to your airspeed in the air. Nice work on the blow-in doors. I suspect it was simply air movement holding them closed.

Great video Ben! I’m considering getting back into the hobby and live in Birmingham! I need to look into a flying field soon. Which plane did you prefer, the F4 or F18? I’m looking at building those two or the F16 painted as a red tail.

That was so much fun, I really enjoyed this, ben! Thank you for committing to share the build and test flight process with us! In watching your video and the problem with airflow, I wonder could it also be slow flight, sharp turn, really big jet, disrupted airflow to the major air inlet? You're already used to the f-18, but that has different architecture, with dedicated airflow to each side, a shorter main air duct from the inlet, and I believe the F-18 chines are designed to help channel air flow over the airframe and possibly the air inlets as well?

Is this an easy ish jet to fly, also is it easier than the f18?

What is the tape you use for structural support on the bottom and leading edges of the wings?

Why not move the holes to the top of the fuselage instead of the bottom?

Hi Ben I think your cart wheels are too small. Find a discarded baby carriage, those wheels should do really nice for cart OR WW1 aircraft, bush planes etc

I cringed when you landed on the pavement... eek.