Which reminds me… We always flew with the baggage door locked (Cessna 172K and 182L). Years ago I heard someone say that they always flew with the baggage door unlocked. In case of a crash, they’d have another emergency exit.
What’s the current thinking?
Speaking of dad’s airplanes, I looked up his 1968 Skylane to see where it is. It appears to still be owned by the same guy who owned it a couple of decades (or longer) ago. A recent photo shows it still wears the paint scheme and colour dad chose back in the '80s. The only difference I see is that it now wears a three-bladed prop. According to FlightAware, it last flew Tuesday, April 6th.
can you open it from the inside? It’s a basic hinged door. Could probably bang it open with a fire extinguisher in an emergency.
My goal would be to always have the door open in an emergency landing. Even if the plane is upside down I should still be able to kick it open further. If it’s jammed into the frame then it’s not going to end well in a fire or water situation.
And what does a 3 bladed prop get you on a 182? Seems like a lot of money to hang on the end of an engine.
IIRC (which I may not), you could open it from the inside if it’s not locked; but it locks from the outside with the key.
Years ago I asked a question (probably in GQ) about when a three-bladed prop (say that three times fast) is useful on a small aircraft. ISTR that at some horsepower a three-bladed prop gets more out of an engine than a two-bladed prop would. I also seem to recall that the 230 hp. engine in the 182 was right on the cusp.
What happens if gear up selected while the plane is on the ground? What happens if you attempt to takeoff while the gear selector is still “up”? Is that what happened in the following YouTube video?
There is a YouTube video entitled, “Mooney Crash”. The still picture shows 20+ people lifting a Mooney up by the wings and fuselage. The video shows the Mooney starting the takeoff roll. At about the point where the plane would become airborne, all three wheels retract and the plane is doing 60 MPH on it’s belly. The end of the video shows the plane being hand-lifted and the gear lowered and then pushed back to the hangar.
I believe you mean this vid:
The specifics depend on the model of airplane.
In some / many / most(?) planes you can’t even move the handle to “up” on the ground; an electrical switch knows the airplane is on the ground and drive a solenoid to push a locking pin into the handle so it can’t move. Of course that system can malfunction or be overridden. The switch(es) typically work by sensing “airborne” when the gear leg(s) fully extend, meaning there’s no longer any weight on the wheels. Absent that the switch senses “on the ground”
Different aircraft use different means to power the gear motion. Some are electric motors, others are hydraulics powered by either an electrically-driven or engine-driven pump.
As well, different aircraft’s gear have different geometry on the ground. Some have over-center links that mechanically lock the gear in the down position and the power actuating system lacks the oomph to throw those links over-center to begin retraction if there’s any/much weight still on the gear. Others don’t have that, or at least not on all 3 gear. Instead they rely on hydraulic pressure, gear train resistance, etc., to hold the gear in place. Typically high wing lightplanes like this:
rely on gear geometry to protect against inadvertent retraction, at least of the mains. There’s just no way the retract system has the power to shove the legs down and inward like that while the aircraft’s weight is on them. For sure the moment the airplane actually lifts off they can begin retracting. Which would be a bad surprise for the pilot.
This wiki section has a good animation of an over-center link and the next section down has 3 pix of low wing lightplane retractable main gear to give an idea of how that stuff might work. Unfortunately the Mooney-specific picture shows some aspects of the suspension, but none of the retraction system.
Would they really put a squat switch on the nosegear? That doesn’t make a lot of sense to me. I would expect that to lead to exactly this tyoe of problem. The airplane isn’t flying until the weight is off the mains.
Older Moonies, btw, had a completely manual gear system using a big ‘Johnson bar’ in the cabi to manually move the gear through a series of linkages. That’s what our Club’s Mooney had. I loved that. Very positive indication, no chance of accidentally moving the gear switch, no motors, and super fast. Gear down in one second.
The biggest drawback is probably a human factors one - it requires significant motion and effort in the cabin to put the gear down, and you are doing this while on final, low and slow. Still I’ve never heard of a pikot losing control while wrestling with the gear.
Good question. Without hunting down a Mooney manual after figuring out which year and model is in the vid I can’t answer that.
With the manual system you describe, I wonder what happens if you get it almost into the fully down position then land? Instant gear fold? Or does the gear tend to hold but then fold on the next takeoff? That might be what we’re watching. Or a linkage failure someplace along the chain of moving parts.
The manual gear goes over-center, and there’s a big metal lock on the panel that it locks into when you put the gear down. But I believe that if yoh pushed the gear lever up to the panel but didn’t fully lock it, the gear would still stay down.
You’d have to leave the lever somewhere in the kiddle before the gear would collapse, and that would be incredibky obvious, I think it’s a really safe system, and also simple and low maintenance, If that handle is locked in place, the gear is down and locked.
If I remember correctly there was an incident where a mechanic dropped a DC-3 by retracting the gear. There’s a by-pass switch on the lockout mechanism so you can do gear swings.
Pretty much any “can’t retract on the ground” lockout has a defeat switch in the cockpit. Often right next to the gear handle. The issue being that if you have a takeoff engine failure and if somehow that mechanism fails (or becomes unpowered) at the same time, you’d be stuck unable to retract the gear during an engine failure. Which pretty well guarantees a crash nearby.
And yes mistakes get made during maintenance efforts. Pin just two of the three, raise the handle and … Oopsie!
A helicopter crashed into a tour bus in Hong Kong in 2009. The accident report (.pdf), which contains photographs, says:
The investigation concluded the cause of the accident was that the helicopter during a downwind approach experienced a Loss of Tail Rotor Effectiveness (LTE) that resulted in the aircraft spinning to the right during a low airspeed tight turn to the right. This subsequently led to the total Loss of Tail Rotor Effectiveness due to a Vortex Ring State developing on the tail rotor disc.
And:
- Under the effect of a prevailing wind of east-southeast at 16 knots and whilst the helicopter was flown towards the northwest in a downwind condition, the pilot encountered difficulties in stabilising the helicopter and performed a go around. After an uneventful go around, the pilot made a second approach at 0313 hrs (1113 hrs) towards the northwest still in an east-southeast downwind condition (121 degrees) of 1-minute mean wind speed at 17 knots, gusting up to 21 knots, and eventually decided to perform another go around at low airspeed due to difficulties in stabilising the helicopter. As he was making a turn to the right, the helicopter started a spin in a clockwise direction. Whilst the helicopter was spinning, it began to lose altitude and drifted in a northerly direction until it impacted the windscreen of a coach parked in the parking lot adjacent to Sung Wong Toi Road.
We practiced getting into and out of vortex ring state once in training. This was making the main rotor enter the state. I don’t recall ever hearing about vortex ring state on the tail rotor, but now that I have it seems obvious – especially with those winds.
Not trying to be a sharp-shooter here, but from the pilot POV you (any you) always need to append “… unless something downstream of the handle I see/touch is broken, loose, out of adjustment, or disconnected.” to nearly every sentence about the correct functioning of any system, be it mechanical, electric, hydraulic, or software.
To be sure, the simpler it is the less that can go wrong. And that Mooney manual gear is a pretty darn simple system. I’m speaking more about a mental attitude than about a piece of hardware.
I’m no helo driver, but there’s some real nice explanations of helo low speed aerodynamics in there. Basically PDF pages 36-48.
He was inadvertently and unknowingly exploring the extreme edges of his aircraft’s envelope and strayed over the edge into dynamic loss of control.
But as you’ve said in earlier posts about many helo mishaps, the aircraft is trashed, but the people walk away all but unscathed. One of the nice things about centrifugal force is that all the high kinetic energy chunks of the helo want to scatter far from the cabin in the middle once they’re set free.
Sure. A broken linkage would ruin your day. There have been gear failures in M20C’s with the manual gear. It’s just that you notice them right away because either the bar won’t move (one accident had the gear jam in the wells after retraction and wouldn’t come down again), or you’ll feel it if a linkage is broken because of the low resistance of the bar.
We had a pilot retract the gear on the Mooney and fly hundreds of miles with the towbar still attached to the nose gear. Somehow he managed to get the gear down and land without damage to the gear, and without bouncing the towbar into the prop. He had no idea what he had done until he got out of the plane.
That was the second-last time he flew with us. The last time, he ignored a NOTAM and flew through an active military jump zone. That was the end of his flying days with us. And we had lots of 'splainin to do to the controllers on base.
Good on your club for having the cojones to “fire” that guy. “Won’t learn” is in many ways worse than “Can’t learn”.
Makes me wonder why that they don’t put a small propeller over the collective to counter this effect.
Huh? I’m not visualising what you’re suggesting.
I’m standing in left field on this but if there’s a vortex generated in the center of the rotors then put a small propeller (above or below) the center of where there is no lifting surface to block it.
If nothing else put in a sensor that sees the vortex so the pilot has a stall warning indicator.
there was an engineer in Ohio who built a helicopter with a propeller below the engine in addition to the rotor. The engine was housed in a bell shaped funnel and there were 3 vanes below the propeller that steered the helicopter. It was test flown and that was the end of it because it was a commissioned work and the company that paid for it shelved it.
I wish I’d copied a picture of it. Can’t find any reference to it. Per the designer it had been filmed flying by one of those short-real film companies.
the reason I bring it up is that curved funnel would have pulled air down and may have prevented vortexes in the center of the mast.