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Old 08-15-2022, 06:12 PM
  #6  
joepilot
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Joined APC: Jul 2008
Position: 747 Captain (Ret,)
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Originally Posted by JohnBurke View Post
Much as I love listening to talking heads spout off their expertise (saving investigative teams one or two years of work in the process), Juan brown doesn't have a damn clue what he's talking about here, regarding conventional gear operations or the DC-3 (he asks if the flaps just bled back up on their own with loss of hydraulic pressure...ah...NO. Open center systems don't work that way). He carries on about the mishap, then notes that he doesn't know if it was a landing or a takeoff. He comments about the flaps extended during the roll, but retracted after the aircraft came to a rest; they appear retracted during the roll. The video is grainy.

It is reported as a landing.

There are numerous reasons that control might be lost during landing on a multi-engine conventional gear airplane that could run the gamut from brake or gear or tire problems, to beta, reverse, or engine, governor, or propeller problems, to runway condition, to pilot action, to gusting conditions.

Rudder effectiveness is not lost by bringing the tail down, but may be diminished. If asymmetric thrust (due to engine failure or due to an engine-trim, beta issue, or other cause) might necessitate getting the tailwheel down and braking. Juan seems preoccupied with the jet mentality of weight on wheels for brake effectiveness. There is no anti-skid on the DC-3, and generally it's a very slow airplane. There are no spoilers, and while one might reduce weight on the wheels slightly by bringing the tail down early, getting the tail down is a typical way to increase control in a crosswind, and to get a third point on the ground.

The video has the appearance of a fast landing with a braking attempt that's excessive, causing the airplane to pitch forward, and the pilot attempting to counter it with back pressure, forcing the tail down.

Without knowing the tire or brake condition, pilot experience, field conditions, maintenance status, rigging and trim setup on the engines, specifics of what occurred, and so on, then it's irresponsible to guess. Juan Brown posts his picture talking out his backside often enough, sometimes far out of his depth and this appears to be such a case. Not a fan of Juan or Dan, or their commentary. Brown shows a different airplane landing and tries to assert that the technique (wheel landing) used in that landing is THE way to fly the DC-3. It isn't. More than one way to skin a cat. More than one one road to Rome, and all. The DC-3 can be wheel landed, and can also be three-pointed.

Raising flaps on landing is a common method of avoiding flap damage, getting the tail down, and putting weight on wheels. Juan apparently doesn't know that, and from his perspective as an airline pilot, it might seem to him, as heresy. On dirt runways or rough fields, it's a useful practice.

DC-3 brakes, originally expander tube rubber-impregnated canvas bladders, tend to get hot and fade, like most brakes of airplanes of the same era. If applying heavy braking on landing, especially so much that one is having to apply elevator to counter the pitching tendency, it's very possible on a fast landing to get the brakes hot and to have one fade; the result is that the airplane will turn toward the good brake, and I've seen airplanes depart the runway this way.

Getting the tail down...getting the tail down with a locked tailwheel gives some directional stability to the airplane. The downside is that with a locked tailwheel, if the airplane isn't pointed where you want it to go once the tail is down, it's going whatever direction it was pointed. This means that if the airplane is pointed anywhere other than a straight line down the runway, then it's going anywhere other than a straight line down the runway. Get the tailwheel on the ground while pointed on a line that takes the airplane off the runway, then that's where it's headed. Off the runway. If one tries to keep it on the runway and retract the tailwheel lock, any side motion on the tailwheel will not allow the lock to retract, and one is likely to break the cable before one is able to unlock the tailwheel. The correct method is to wiggle the tail slightly, either using rudder or alternating differential braking, to take the load off the tailwheel lock, to retract it and allow the tailwheel to caster, in order to use differential braking (and thrust) for ground control.

The video appeared to show a fast landing and rollout, with an attempt to use heavy braking to get the airplane stopped, with a loss of directional control in the process. Once the airplane starts that turn and sideloads the tailwheel, there's no more control, and if braking action has already caused fade, then one is along for the ride.

Again, it's impossible to make any definitive statement from that video, which is grainy, incomplete, shot from far away, and leaves out too much information. The DC-3 doens't need much brake, as a rule, when landing. It has a lot of wing. It takes off slowly, lands slowly, and with no wind or wind down the runway, does just fine holding the tail in the air as it slows without much braking action at all.

This being a turbine conversion, if the pilot attempted to use an beta or reverse with the tail in the air, there's a definite possibility of a loss of control, and in any case, if the pilot put the tail on the ground (let it come down or forced it there) with any degree of side load, it was going to go in whatever direction it was pointed once the tail was on the ground, and the tailwheel lock would have prevented directional control via differential braking or thrust beyond only very slight changes...nothing significant with any speed.

The most dangerous part of conventional gear flying is the transition tail up, and tail down on takeoff and landing, and operations in which rudder effectiveness is lost or reduced (quartering tailwind, for example.

Juan really wants to see that tail stay in the air until it can't fly any more and then come down (land the mains, landn the tail), and one can get the tail up there standing still, with a little power), but any differential issues, whether it's braking or thrust (which could be reverse or beta, not necessarily asymmetric positive thrust), and hovering that tail like he thinks should be done, and like he compares to a normal landing in low-wind, isn't advisable. The tail needs to get down to maintain control, along with differential braking. The DC-3 at low speeds is primarily turned and controlled with differential power, supported by differential braking. At higher speeds (an oxymoron in the DC-3), via rudder, when there's rudder effectives (and NO asymmetric condition: brakes or engines/propellers/runway). In between, it's varying degrees of rudder and differential braking.

Juan shows a DC3 taking off and states that "you want to get the tail up as quickly as possible," suggesting that's proper technique. Push that power up, and the tail tends to come up, and will stand up and can be flown with some power on the engines, even with the brakes held. The airplane can be flown off the ground three point and landed three point, but generally isn't. Getting that tail in the air too soon is asking for trouble in gusting crosswinds, or in the event of an asymmetry. An asymmetry might be an engine failure, but could also be a beta tube issue on the engine, a governor issue, a hung brake or even a pothole; anything that causes a directional control issue. It's well to enjoy the tail up, the visibility, and the acceleration when everything is operating normally; that free lunch loses it's snap when one fan quits or rolls back and that free airflow on one side is no longer on the menu. At that point, assuming directional control isn't already lost, getting the other engine quieted down, or retaining adequate braking, may be the ONLY options, especially as rudder effectiveness is not what it was two seconds ago. Juan Browns commentary doesn't seem to understand this basic concept.

And it's the big cargo doors that make this airplane such a great performer for these remote...hold on a second, Juan. This was a passenger flight. Six passengers on board. Two crew. And cargo doors don't equate to performance. It seems that sometimes he simply talks because he likes the sound of his own voice because what he's saying isn't remotely true, and makes no sense.

Juan Brown alludes to his Husky, for his conventional gear (tailwheel) knowledge and experience...which doesn't necessarily translate to flying the DC-3. He doesn't have a very good grasp of the airplane systems or procedures, or how to fly the airplane, and his non-sequitur straw-man allusion to other unrelated videos and operations are a bit of a head-scratcher.

I'm sure he makes some money from the videos and advertisements and his patreon, offering up all kinds of insider knowledge and being the first to have the scoop on what "really happened," even if he has to make it up as he goes. I usually don't bother watching, because every time I do, the miniscule level of respect I might have had, slips further, and it's videos such as this which are a prime example.
Hi John.

Thank you for the informed information on this incident. I have never flown a tailwheel (except for gliders), so I don't know what I don't know. See my avatar.

Joe
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