The illusion no one mentions

Pi1otguy

Pattern Altitude
Joined
Oct 24, 2007
Messages
2,463
Location
Fontana, CA
Display Name

Display name:
Fox McCloud
I wonder if I'm the only one who has to fight this illusion on short final? One that made setting up the proper side slip or doing a good crab-kick correctly.

The initial tendency to look over the spinner when aligning instead of straight ahead. In the pic imagine the pilot is the blue dot (position exaggerated). The yellow line is the correct path straight ahead and leads to landings with no sideload. The red line is looking slightly right to the pointy bits and sends you off the side off the runway.

9cp5RLgcE~2.jpg
 
I think everybody does until they move past it. Some move past without even realizing it. I have to think about it. A couple planes I actually lined the plane up to a tree or pole a few thousand feet away and then sat in the plane and marked the spot on the console that’s actually pointing to the tree. Helps me.

I had an instructor in a Pipistrel that constantly screamed at me to add rudder and I yelled back I didn’t need it. We actually fought each other all the way down final because I swore I was right. He taught me the above trick, and damned if he wasn’t right.
 
A couple planes I actually lined the plane up to a tree or pole a few thousand feet away and then sat in the plane and marked the spot on the console that’s actually pointing to the tree.
Most 172s have a lot of rivets. I use a row of rivets that I look parallel too.

Now aircraft without rivets...
 
I wonder if I'm the only one who has to fight this illusion on short final? One that made setting up the proper side slip or doing a good crab-kick correctly.

The initial tendency to look over the spinner when aligning instead of straight ahead. In the pic imagine the pilot is the blue dot (position exaggerated). The yellow line is the correct path straight ahead and leads to landings with no sideload. The red line is looking slightly right to the pointy bits and sends you off the side off the runway.

View attachment 107232
Good point, I had a lot of struggle with this at first. We get spoiled in our cars that just go where they are pointed then we get in a vehicle where yaw is arbitrary and you have to control it.

The method @Salty described works great, before you get in, stand behind it, see where its pointing(find a landmark), get in, see where that lines up with where you're sitting and the view out the window!
 
I've never had this issue. Maybe it was having trained at and based at a somewhat narrow 36' runway. A 50 footer feels immense.
 
Further, it is bad form to land on the centerline........especially in a jet with high-pressure tires. The .....thump.....thump....thump.....of the centerline lighting is rough and noisy.

We always tried to run the centerline right between our legs. That put the lights a few inches off and also gave a great way of lining up straight since the CL went right through the center of your vision and body.
 
I wonder if I'm the only one who has to fight this illusion on short final? One that made setting up the proper side slip or doing a good crab-kick correctly.

The initial tendency to look over the spinner when aligning instead of straight ahead. In the pic imagine the pilot is the blue dot (position exaggerated). The yellow line is the correct path straight ahead and leads to landings with no sideload. The red line is looking slightly right to the pointy bits and sends you off the side off the runway.

View attachment 107232
You can get that resolved when your taxiing. Find the sight picture that puts the plane on the center line. Get a grease pencil and put a little smudge on the cowling, or windshield. I Don't really mean that, just illustrating the point to find out what on the center line looks like in the plane you fly from the seat you sit in.
 
I’m not completely following, your saying rather than looking straight ahead you are/were looking to the right across the spinner? So crabbing down to the runway?
 
I’m not completely following, your saying rather than looking straight ahead you are/were looking to the right across the spinner? So crabbing down to the runway?
It's very slight but yes. It's overcome after a few hours in make and model, but is something to actively keep in mind.

Mainly, I wonder why it's something we just figure out and compensate for on our own vs it being listed as one of the illusions we are taught about.
 
It's very slight but yes. It's overcome after a few hours in make and model, but is something to actively keep in mind.

Mainly, I wonder why it's something we just figure out and compensate for on our own vs it being listed as one of the illusions we are taught about.
It’s not an “illusion”, it’s “parallax”. Normally it comes up in primary training because students tend to need guidance in the proper reference points. It also comes up frequently during instructor training when pilots move to the right seat (you’ll find several threads here if you search the right combination of words.) transitioning to or from tandem airplanes is another common time.
 
It’s not an “illusion”, it’s “parallax”. Normally it comes up in primary training because students tend to need guidance in the proper reference points. It also comes up frequently during instructor training when pilots move to the right seat (you’ll find several threads here if you search the right combination of words.) transitioning to or from tandem airplanes is another common time.
Parallax causes it, but it’s still an illusion.
 
I don't think I've ever thought of it. I look down the runway and kick is straight. I never have an issue with alignment. When I got back into flying I did land a little misaligned once or twice. The plane jerks when you land and your hip bumps the door or center console for very slight misalignment. I've never done worse than that. I think the key is to not look in close to the airplane, but down the runway. If you think about it too much it will become an issue.
 
When I got back into flying I did land a little misaligned once or twice. The plane jerks when you land and your hip bumps the door or center console for very slight misalignment.

Learning tailwheel helped me greatly to overcome setting the plane down misaligned. Flying with a friend one day he had a landing that the sideways pull was quite noticeable. I remarked that he wouldn't have gotten away with that landing in a tailwheel plane.

Don't misunderstand ... I'm still a newbie tail wheeler and now and then I still have to get very busy doing the pedal dance if I don't get the touchdown correct.
 
Learning tailwheel helped me greatly to overcome setting the plane down misaligned. Flying with a friend one day he had a landing that the sideways pull was quite noticeable. I remarked that he wouldn't have gotten away with that landing in a tailwheel plane.

Don't misunderstand ... I'm still a newbie tail wheeler and now and then I still have to get very busy doing the pedal dance if I don't get the touchdown correct.

Ill second this! I still have some I’m not proud of but man can I grease in a nose dragger now :)
 
Parallax is especially bad in a helicopter when landing and turning. Any time I see a pilot climbing and descending in level turns, it is obvious they are not using a reference directly in front of their eyes.

When I see this, I have them turn the nose 45 degrees or so to the landing heading to break the habit of using some arbitrary piece of the aircraft as a reference.

They way I teach it, I refer to the fact that as Americans, we have grown up driving big cars with hood ornaments in the center of the hood (not so much any more) and always being on the left side of the centerline of the vehicle. Ever notice people at the drive-through running over the curb? Yeah, parallax...
 
Learning tailwheel helped me greatly to overcome setting the plane down misaligned. Flying with a friend one day he had a landing that the sideways pull was quite noticeable. I remarked that he wouldn't have gotten away with that landing in a tailwheel plane.

Don't misunderstand ... I'm still a newbie tail wheeler and now and then I still have to get very busy doing the pedal dance if I don't get the touchdown correct.

I'm pretty busy on the rudder with a nose wheel plane with a gusty crosswind. Thinking about a tailwheel endorsement this summer.
 
Maybe it's "never mentioned" because you get past it after the second or third landing attempt. There are lots of "illusions" in flight that you just adapt to.
 
I just put the centerline between my knees and it all works out
 
They don’t mention this cause not everyone has this problem. Shouldn’t you be looking down the runway on landing and not focused on something too close by?
 
They don’t mention this cause not everyone has this problem. Shouldn’t you be looking down the runway on landing and not focused on something too close by?
Who says he wasn’t? Peripheral vision and all.

Once upon a time in a career long ago, I was a newly minted Airbus 320 First Officer. I had spent the previous 5 years and 3,500 hours flying the 737-300 series Boeings. Neither aircraft has any nose structure visible out of the windscreen so you have to get your visual cues elsewhere.

One day, after flying with me for three days, my Captain said that I was consistently landing in a slight crab. When he demonstrated what he was talking about, I realized he was right. I figured out that I was using the same sight picture that I had been using with the 737. The Airbus was enough different that I was landing in a crab.

I guess the moral of the story is that until someone points it out, one might not know he is doing it wrong, or not know WHY it is wrong.
 
Find the sight picture that puts the plane on the center line. Get a grease pencil and put a little smudge on the cowling, or windshield. I Don't really mean that,
Wait, you mean I shouldn’t have drawn a mil-dot rangefinding reticle inside the windscreen with a Sharpie?
 
Just a small sampling of examples of no one mentioning it on POA. ;)

it took me at least several flights before I could land on the centerline, and without a side load. Heck I had trouble taking off on the centerline too!

such as landing well right of the centerline in a crab toward the center (just as students tend to land well left of the centerline).

Just be prepared for some pretty intense sideloading on your first few landings. The sight picture can play tricks on you.

The sight picture and trying to keep the longitudinal axis of the airplane centered on the runway takes some getting used to.

majority of right seat first timers will try and land pretty crooked due to the difference in sight picture.
 
Correct. A grease pencil is the only authorized utensil.

Bugs are an acceptable marking method on the outside.

Unless you wanna make it real:

proxy-image
 
Switch over to the right seat and the airplane tends to ease to the right all by itself...
 
I just make the stripes line up and call it good :dunno:
 
Actually, if your not taking out the blue lights, its ok:cool:

Cheers
 
You can get that resolved when your taxiing. Find the sight picture that puts the plane on the center line. Get a grease pencil and put a little smudge on the cowling, or windshield. I Don't really mean that, just illustrating the point to find out what on the center line looks like in the plane you fly from the seat you sit in.
We literally had a convenient rivet line.
 
It's a problem, OP, because you aren't looking far enough down the runway.
 
When I was first learning to drive I used to line up the stripe at the edge of the road with the edge of the hood. Once I learned how to look straight ahead and keep the car centered I stopped doing that.

Landing the plane is kind of the same thing.
 
It could be if the runway is 24 feet wide and your wingspan is 35 feet with main gear spanning 10 feet.
Or 20’ between the trees with a 28’ wingspan…first year the tips of the trees brushed the ailerons when I set the tail down. Second year they were brushing the leading edges, so I had to quit landing there.
 
It could be if the runway is 24 feet wide and your wingspan is 35 feet with main gear spanning 10 feet.


I usually mow my runway to 20' wide, the wings just pass over the hay, as its a high wing being a 180. No center line, but if a couple feet off center, no concern.
 
Back
Top