Locating the runway

[Henning]

Now there's one to have with Google Glass!

Not available on android though...

 

[JeffDG]

Doe the airport have an instrument approach? If so, fly it.

Bing!

I had that happen on my night-XC with the instructor...we were less than 5 miles from the airport and couldn't see the damn thing (it was towered, but that's not the point).

Now, especially at night, I'll put in an instrument approach...gets me all nice and lined up with the runway.

 

[MAKG1]

Holy crap, that is cool...

IF it works. If it uses GPS to determine attitude, it won't include WCA. And if it's anything like Google Sky Map, it will place stuff 10 deg off, probably bad enough to land at the wrong airport.

 

[Jim Logajan]

IF it works. If it uses GPS to determine attitude, it won't include WCA. And if it's anything like Google Sky Map, it will place stuff 10 deg off, probably bad enough to land at the wrong airport.

I'm willing to spend $10 on an experiment so I just bought it for my iPhone 4s. Have only had a chance to use it in my office so far. Really is kinda neat.

It uses the electronic compass in the iPhone/iPad to determine orientation, GPS to determine location, and an internal database of airport locations. Then it uses all that info and the camera to paint whatever the camera sees onto the screen and overlays markers on it showing where the airports should be. I really can't tell while sitting in my office how close it gets, but so far seems about right. My home airport appears to be behind the bookshelf....

Oh - something I didn't realize, but the compass in the iPhone 4s seems to work just fine oriented in all three axis and right side up or upside down.

 

[eetrojan]

So hypothetical... possibly common scenario:

You are inbound for landing at an uncontrolled airport you've never been to before. You know what runway you want based on winds, the gps is telling you it's right in front of you 5 or 6 miles ahead. You know about where it should be in relation to nearby landmarks but your eyeballs just won't locate the runway so you can set up for a proper pattern entry and landing.

What's the ideal response to this?

Here's a tip that my CFI gave me that may help you find the runway in the first place.

My trainer has an HSI, so it's compass card always rotates to match my heading. As such, it's useful for quickly figuring out how the runway that I'm looking for lies relative to my point of view on my current heading.

For example, if I were inbound to Runway 26 while flying on a magnetic heading of 010, I could use the HSI to help find the runway as follows. First, I find the 8-26 line on the HSI and imagine that it's the runway. Then, I move that imaginary runway out ahead of my aircraft, something like the diagram below.

I usually forget to do this, but it was VERY helpful on my first night flight.

 

[MAKG1]

Oh - something I didn't realize, but the compass in the iPhone 4s seems to work just fine oriented in all three axis and right side up or upside down.

Actually, that's a sign of BS from the phone. A real compass has two directions in 3D space where the measurement is poorly defined. It's very much like the zone of confusion for a VOR, except it's not zenith/nadir.

 

[Jim Logajan]

Actually, that's a sign of BS from the phone. A real compass has two directions in 3D space where the measurement is poorly defined. It's very much like the zone of confusion for a VOR, except it's not zenith/nadir.

You are correct when the sensor senses on only 2 axis. However, according to net sources, the iPhone 4 uses the 3 axis AKM AK8975 hall effect chip:

http://www.akm.com/akm/en/product/datasheet1/?partno=AK8975

 

[cowman]

Good responses, thanks.

I really do think it's an art and so far it's an art I'm not great at. I've had trouble seeing one with my gps and my instructor in the right seat pointing right at it. Up here, most of the time you're not so much looking for the runway it's self but a clearing in the trees/fields/etc big enough and in the right place.

I have to confess this wasn't completely hypothetical.. I did my first real cross country the other day and found myself in this situation. I'd been doing so well at finding my home airport and another that I'd flown to with my CFI many times that I was confident. I'd studied the google satellite view the night before and "knew" where the airport would be in relation to the town. I had a garmin 430, foreflight, and a VOR to follow on top of that.

And yeah all that got me there all right.... I spotted the runway off my right wing pretty much at pattern altitude. Which in this case meant I was exactly where I'd wanted to be..... except going the wrong way. And just to reinforce it if isn't obvious... this means I'm going opposite to traffic flow for the best runway for wind conditions which is not good.

In that case no big deal, there was no other traffic and I'd been on the radio and scanning visually for traffic but I realize I shouldn't have put myself there in the first place. I think that on my next flight I will maintain a higher altitude until the field is in sight, and make more of an effort to approach the general area from the direction I need to enter the pattern from. This seems obvious in hindsight but it just never came up during my training, I always had someone familiar with the area in the right seat giving me "vectors" until I had the runway in sight. We'd always done decent planning to have me at pattern altitude when we entered the pattern... which is the procedure I continued to follow and shouldn't have

I also paid some more attention to how I was finding my home field on the way back. And indeed I'd again spotted it at over 10 miles out. I realized that I don't really see the runway until I'm actually less than 5 miles.. maybe closer to 3 miles away. What I see is the clearing in the right shape, by the river in the right place relative to the town. I know where the runways are, but picking them out without knowing where they are? Still hard...

For reference, my home field from airnav..

Picking out the slightly darker tan from a lower altitude 5-10 miles out isn't easy.

 

[Matthew]

One problem with not seeing an airport is you can get fixated on finding it and forget to scan for traffic. Staying high, above tpa, can give you a better view.

My CFI told me to look for the airport environment - clearing, hangars, whatever. There is usually something that gives it away from a distance. Still, sometimes it's just hard to see some airports from some angles.

 

[Blatham489]

You do know Foreflight has VFR approaches built in now, right? In edit mode, (assuming your destination has been selected in your planned route) click on Procedures, then Traffic Pattern, then select the runway and entry type, it even suggests the best entry based on location and winds. Just used it a few days ago for a night landing at an unfamiliar field. Slick.

 

[MAKG1]

You are correct when the sensor senses on only 2 axis. However, according to net sources, the iPhone 4 uses the 3 axis AKM AK8975 hall effect chip:

http://www.akm.com/akm/en/product/datasheet1/?partno=AK8975

That doesn't change basic geometric constraints that magnetic field lines are inherently one dimensional, and attitude is not determined orthogonal to that. There must be additional constraints. If they assume you're looking at the horizon, that's only going to work for distant airports. And, as a toy, we don't know how accurately it can find the field direction, or if it has any knowlege of local distortion, which can be substantial.

What it does mean is that it can sense the dip angle, and should therefore not show the usual mag compass errors.

 

[pbramlett]

Some airports are just danged hard to see when you're coming in for the first time ever. Hidden by trees or hills. Buried in a mass of buildings, etc.

I too try to look at a new field on google maps or earth and get a feel for it. Just knowing which side of a small town a small airport is located is extremely helpful.

There's only one that I found repeatedly hard to find. Hartselle, AL (5M0)...which was a fuel stop when I was working in Georgia. A north/south runway completely hidden behind trees when coming in from the west. Many times I'd be right on top of it before seeing it.

I was going to say Hartselle. I was based there for two years and found it annoyingly difficult to find if coming in from the east or west. Just a difficult airport to spot.

 

[Jim Logajan]

That doesn't change basic geometric constraints that magnetic field lines are inherently one dimensional, and attitude is not determined orthogonal to that. There must be additional constraints. If they assume you're looking at the horizon, that's only going to work for distant airports.

The app appears to also use either the 3 axis accelerometers in the iPhone or assumes the field lines are parallel with the earth surface (unless he's taking into account the local dip) - because when I tilt the phone up or down, the airport markers shift down or up so they try to maintain their locations on the background image being displayed. There is some hysteresis and lag that seems to cause as much as +/- 15 degree movement against the background if I pan rapidly - much less than that if I pan slowly. However, it doesn't work at all correctly when the phone is tilted so the horizon isn't parallel with bottom of the screen. If he did a better job of using the accelerometers the program probably could be made to handle a tilted screen.

And, as a toy, we don't know how accurately it can find the field direction, or if it has any knowlege of local distortion, which can be substantial.

Not sure the point of calling it a toy just because the accuracy isn't known - given the option of not having it at all, which is perfectly reasonable option. Since many pilots already fly for the enjoyment anyway, the whole bloody plane and all the stuff in the typical flight bag are "toys". I spend about a $90 for an hour of flying - a one time purchase of a $10 app isn't that big of a deal to me. I don't know that I'll ever find it helpful, but I do think it is neat and clever.

What it does mean is that it can sense the dip angle, and should therefore not show the usual mag compass errors.

It is true that Hall sensors will not exhibit any of the problems of a mechanical wet compass. They require power, but will have a great advantage during turns and turbulent conditions.

 

[MadseasoN]

One thing that can help - visually draw an imaginary line across the DG between the runway headings. You can find the airport easier if you know which way the RWY is oriented in relation to your heading.

 

[timfountain]

One of my most difficult situations was where I was inside PDX (Portland) airspace going to TTD (Troutdale) and they were keeping be "at or below 1,200 ft" for spacing to the heavy metal going into PDX and although I was only 2 miles away and had the airport on the GPS, I still had no visual on it 'till I was almost on top of it.

The slant angle to the airport on the nose, combined with the dense urban area around the airport made it very challenging. This was one situation where climbing to get a better overview of the terrain was not possible.

 

[Henning]

One of my most difficult situations was where I was inside PDX (Portland) airspace going to TTD (Troutdale) and they were keeping be "at or below 1,200 ft" for spacing to the heavy metal going into PDX and although I was only 2 miles away and had the airport on the GPS, I still had no visual on it 'till I was almost on top of it.

The slant angle to the airport on the nose, combined with the dense urban area around the airport made it very challenging. This was one situation where climbing to get a better overview of the terrain was not possible.

If you're on the radio with ATC already, just say "negative contact on the field, could I get a vector and range please?"

 

[MAKG1]

If you were inside the PDX Class C at 1200, there is an enormous river and a major interstate leading the way to TTD.

Sometimes we get so enamored with gadgets that we forget to look out the window.

 

[Palmpilot]

Not always possible; most approaches are GPS approaches, and not all aircraft are GPS equipped.

Not always desired, as instrument approaches can take you miles out of your way, and put you in front of much faster aircraft.

Many handhelds have the final segment of the approach course, which is all you need when you're VFR, and you are free to intercept it as close to the airport as you find convenient.

Alternatively, many of them have the final approach depicted even when there is no instrument approach.

 

[timfountain]

If you're on the radio with ATC already, just say "negative contact on the field, could I get a vector and range please?"

Oh yeah, versions of that were said many times. Tower were telling me it was 12:00 3-4 miles but I just couldn't see it. Problem was really the slant angle, you just couldn't see the wood for the trees at that altitude....

 

[timfountain]

If you were inside the PDX Class C at 1200, there is an enormous river and a major interstate leading the way to TTD.

Sometimes we get so enamored with gadgets that we forget to look out the window.

Thank you. Heads were up and locked but the airport wasn't visible given the slant angle to it in the dense urban surroundings. I was coming from the south and at that low alt and 3-4 miles out, neither I84 or the river were particularly visible.
Gadgets weren't the problem, not sure why you had to go off on one about that issue. The original theme of this thread was problematic visual acquisition of airport and runways and I was relating my experience one time in 1000's of landings where I knew where the airport was supposed to be, but I just couldn't see it.

 

[Henning]

Oh yeah, versions of that were said many times. Tower were telling me it was 12:00 3-4 miles but I just couldn't see it. Problem was really the slant angle, you just couldn't see the wood for the trees at that altitude....

Yep, sometimes the conditions are such you don't see it until the last moment, you just operate on faith and set the plane up according to the distance from where it must be.

 

[asechrest]

In my neck of the woods, the ones nestled in an urban area seem most difficult. KCLW was tough the first time.

 

[rcsoar4fun]

I fly in south Texas where everything is flat, brown and windy. The biggest asset I have found for any unfamiliar runway is to set the bug on the direction gyro. That way I know what direction the runway should be running even wen I change my direction searching for it. The bug also gives me a quick reference to make sure I am not encroaching on the runway while on downwind.

 

[saintlfd]

As a student pilot, I find it encouraging to know even experienced pilots can find it challenging to locate their desired airport/runway. My instructor made me feel like a miserable, hopeless failure when I failed to spot a small airport on the outskirts of our metro area. I was almost on top of it before I recognized it, altho I knew it had to be nearby.

This experience shook me so badly I quit flying. What kind of pilot can't find his runway, for goodness sake?

Maybe I will get up the nerve to find a decent CFI and try again.

 

[PilotAlan]

Maybe I will get up the nerve to find a decent CFI and try again.

Get on it! When you do a cross-country, note every airport within 20 miles of your courseline, and use them as checkpoints. Like everything else, you get better with practice. Picking out airports gets easier as you do it more and more.

 

[ChrisK]

As a student pilot, I find it encouraging to know even experienced pilots can find it challenging to locate their desired airport/runway. My instructor made me feel like a miserable, hopeless failure when I failed to spot a small airport on the outskirts of our metro area. I was almost on top of it before I recognized it, altho I knew it had to be nearby.

This experience shook me so badly I quit flying. What kind of pilot can't find his runway, for goodness sake?

Maybe I will get up the nerve to find a decent CFI and try again.

Here's one where my locals will laugh at me. I always have trouble finding BJJ because it looks like a patch of farmland among other patches of farmland in the middle of nowhere =)

I also have trouble spotting very large airports at a low altitude, particularly when near cities. I landed at CMH yesterday and pretty much took what I thought to be the airport on faith until I finally saw the tower and determined I was right (this was, really, my first landing there not as a passenger). When you're used to landing on a 2000' runway, your brain can't believe that what you're looking at can possibly be an airport! In those cases I just try to find the end of the runway and aim for that.

What this thread says about trying to see an airport <2000' AGL is totally true. Stuff on the ground or perspective just gets in the way. In these situations familiar landmarks help; otherwise, I just keep looking for clues. I've been told experience helps, and I find the more I fly the easier it gets, but some airports....

 

[Matthew]

Sometimes we spend too much effort trying to find the runway. My first CFI just told me to find the "airport environment". Look for something that just seems like it doesn't fit in with the surroundings - an open area in congestion, a congested area surrounded by empty space, low buildings (hangars) in rows. These are all 3-dimensional clues that can sometimes be much easier to see than a flat rwy.

 

[douglas393]

One other thing, and this may have been mentioned before, but airport environments can be quite difficult to pick out when coming in from one direction and can be sticking out like a sore thumb when coming in from a different direction. So if you cannot find the airport circling around where you think it should be from a distance of 5 miles or so may show you where it is. This would be more useful for an uncontrolled airfield obviously.

 

[Palmpilot]

When coming home to Palo Alto Airport, the first part of the airport that I see is the ramp, which covers much more area than the runway.

 

[SoloEqs]

Look for "Airport" stuff -- hangars, buildings in a line with empty space one one side or the other of that line, big letters painted on things or the ground, rectangular ramps, etc -- and "Can't Be Airport" stuff -- water, terrain or man-made features which would prevent an airport from being there.

If you can't see it at 1500 above TPA, try 3000 and turn 45 degrees away from where you think it is supposed to be.

 

[MAKG1]

Look for charted landmarks to find the airport stuff.

You don't just go looking for the ramp at Palo Alto. You look for the radio towers (VPKGO) or the train bridge (charted as such), the point yourself at the 45 (heading 175) and look just beyond the Bayshore. You can get all this off the TAC.

 

[bobmrg]

In the situation of approaching Troutdale from the south, my solution would be to steer well east until I could see the river and then turn left.

To the OP...choose a prominent landmark away from the destination airport, one that you will be able to see from ten miles or so away; in the comfort of the pilot lounge, measure the magnetic course from that landmark to the airport. Now get up in the air, fly to the landmark, and turn to the predetermined course.

Bob Gardner

 

[Xscaliber]

I dunno - finding an airport is half the fun.

I especially like it at night, when you spot the beacon and start working your way to it, only to realize that's the beacon for the wrong airport. It's really fun when they happen to be lined up on your course and you are looking at the far beacon and miss the one right under your nose.

Been there done that....

 

[weilke]

Been there done that....

Then there is the option to mistake the first airport you encounter for the one you wanted to go to. That is a how a C17 ended up landing on the 3600ft runway at Peter O Knight instead of McDill AFB .

 

[Matthew]

I was headed north, at night, with a failed DG and vacuum pump. There are two airports, side by side, about 7nm apart. I'm wanting to head to the one on the right, and I'm about 10-15 south. Far enough to see the beacon, but not much else. I can't remember the details, i must have been using the whiskey compass. Winds aloft were such that I had a heckuva crab across the ground. My course was taking me to the airport on the right, but my windscreen was facing the airport on the left, so that was the beacon I fixated on. It led to a couple minutes of confusion until I did a quick sanity check.

 

[Ghery]

As a student pilot, I find it encouraging to know even experienced pilots can find it challenging to locate their desired airport/runway. My instructor made me feel like a miserable, hopeless failure when I failed to spot a small airport on the outskirts of our metro area. I was almost on top of it before I recognized it, altho I knew it had to be nearby.

This experience shook me so badly I quit flying. What kind of pilot can't find his runway, for goodness sake?

Maybe I will get up the nerve to find a decent CFI and try again.

Heck, there's a local airport near here that I never did spot from the air until I saw it from the ground. Airport environment? No, just a cut in the trees. Approach from over the water, then turn to runway heading. Take off in the opposite direction. From the air flying by you'll see it briefly as you go by. Don't feel bad. Find a new CFI and have at it again. Your previous CFI was a poor instructor if he treated you that way.

 

[Jim Logajan]

Heck, there's a local airport near here that I never did spot from the air until I saw it from the ground. Airport environment? No, just a cut in the trees.

Speaking of a cut in the trees, can you spot where the airport is in this photo attachment?