Airline

Airport Diagrams & Reducing Runway Incursions

Making Airport Diagrams (Jeppesen 10-9 pages) Usable. Some of the low hanging fruit of Aviation Safety.

 

The goal of airport diagrams is for pilots to quickly understand their assigned taxi route. We brief an expected route before landing but changes happen and pilots *DO* wind up heads down looking at these charts for too long. Some simple changes to Jeppesen's 10-9's can reduce this time thereby improving safety, reduce repeated instructions, and increase airport flow rate. Here are some examples. Consider how quickly you can figure out the clearances by looking at the different charts.

New York La Guardia LGA

You're at spot 14 and tell ground control you're ready to taxi. He says "taxi to runway 13 via Alpha, Gulf Gulf, Bravo, Echo, hold short of runway 22".

Original chart.

 

New.

 

One powerful way to reduce runway incursions is to keep airline captains focused outside the cockpit while moving. That means minimizing attention spent inside the cockpit such as reading charts. One dramatic improvement with my airline was requiring the after start checklist be completed prior to taxiing.

One area remains, though, that pilots have to look at while taxiing—the airport diagram. For most airlines that is Jeppesen's 10-9 page. And it could use a lot of improvement. The airline doesn't produce these charts but, as a major customer, it should push for improvements.

The goal must be to minimize how long pilots must look at the chart to decipher instructions. A number of visual tools can be employed that have been incorporated in the modified example. It's a given that pilots should try to understand taxi instructions before moving, but sometimes instructions are given, or must be verified, while moving.

To the right, on top, is the current FLL 10-9 page and below that is a modified one. Look at the two diagrams and see which one is quicker to understand the sample instructions. Remember, except for the initial call, a captain may be taxiing the airplane while getting instructions.

Southwest flight 1 is parked on the far east side at terminal one. A crew is getting ready to taxi and gets this:

“Southwest 1, taxi to runway 9L via T, T5, S, hold short of taxiway Q”.

Consider also this one. The flight just landed on runway 13. The crew will most certainly be moving when this instruction comes in.

Southwest 1, turn left when able, left on Delta. Taxi to your gate using Sierra, Bravo, enter the ramp at T2.

Look at both charts to see which are easier to use. Of the pilots I've showed these charts to the answer has been immediately that the second one is.

The pilot is going to take much less time looking at the modified chart to figure (or re-figure if given new instructions while moving) his route. Given the FAA's appropriate emphasis on minimizing runway incursions, that is an important outcome. 

Other elements that could improve usability.

1. Increase the airport diagram size by eliminating surrounding airport features. How many pilots use these charts to know about items such as trees, roads, etc., near the airport? The answer is very few (none that I've talked to). We use them to taxi. The current full chart  gives up 20% of it's width to airport surroundings—valuable chart real estate. Bordering information may be valuable for studying the chart beforehand, but gives up clarity in its primary function, understanding taxi routings especially in a dimly lit cockpit.

2. Use visual icons for the most common taxiway notes. Icons can be overused but, in this case, they can help. The max wingspan notes are the best example since pilots will recognize quicker the need to check if they can use a taxiway. The most common values are max weight and max wingspan (or aircraft model). There's never a minimum wingspan so, if the pilot sees a wing icon with 112' in it, he knows immediately whether or not the note applies to him and can go on to read the rest of it. Importantly, this reduces clutter, too.

3. Further reduce clutter by putting runway numbers in the runway and terminal descriptions in the terminal using white on black.

4. Further reduce clutter by avoiding word descriptions of obvious things wherever possible such as VOR's. Every pilot knows the standard VOR symbol so the word "VOR" is superfluous and adds to clutter. Clarity is improved by having secondary information, such as buildings in a lighter shade of gray.

It's true that charts fall outside the control of the airline but we are, after all, the customer. And we pay dearly for this service—we can have some input. In all likelihood, Jeppesen (Boeing) wants to have a good product but they are like any other business, not wanting to spend money on changes unless the customer really wants them to.

Thanks for listening.

Testing

It seems like these charts will reduce heads-down time for pilots taxiing airplanes but do they? Anyone who respects critical thinking will want to find out using rigorous testing methods so that's what I have done.

Test Protocol with First Scenario

Above is a PDF of one such test so you can see how the research is planned. Other scenarios will be added as time allows and the test will be given to volunteers. Initial, poorly controlled testing (small numbers, differing pilot backgrounds) show a benefit but any science respecting researcher would disregard those numbers. Raw data, when available, will be published.

 

Orlando MCO

 

Original:

 

Modified:

 

Fort Lauderdal FLL

This chart was made before the airport made huge changes to its runways and taxiways but the comparison is valid. This was also done before we were using IPads so my source document is not as clean but you can still clearly get the idea.

 

 

New chart. Notice the tower frequency right on the runway and ground control frequencies just off the runway: exactly where you need them!

 

Las Vegas LAS: Taxi Instruction

These show another feature to speed heads down time. Have the ramp control frequency display in the ramp area where it applies.

 

Consider this scenario: You've landed on runway 1R, turn off at high speed Papa, and ground control says: "Southwest 1 turn right on Delta, Gulf, Charlie, hold short of Bravo 5."

Las Vegas LAS: Communications Error

This actually happened.

The crew, with the captain as "pilot flying" landed on 25L, turned off at A6, was instructed to cross 25R by the tower and call ground. After crossing, the captain slowed or stopped the airplane while the FO called ground but got no response. He looked down and saw that it was the wrong frequency. The captain looked at his Ipad, found the ground control frequency and spoke it out. The FO dialed it in and called again.

FO: Las Vegas Ground, flight xxx clear of 25R to gate C7.

ATC: flight xxx contact ramp on 124.4.

They taxied towards the ramp entrance and called ramp who cleared them into the gate.

Both the captain and FO thought they were given a shorthand clearance to taxi to the ramp which was nearby and contact ground but that's not what had actually happened.

The ground control frequency picked up by the captain turned out to be the East ramp frequency (127.9). That transmission to "call ramp" wasn't ground control, it was East Ramp saying to call West Ramp! In other words, they taxied to the ramp without ever even talking to ground control and didn't realize it until too late.

Had they been using the chart below this would NOT have happened. Ground's frequency is plainly obvious since it's right where they're already looking. By the time they figured out what had happened they were about to turn into the ramp.

Of course more vigilance is always a solution and these pilots will, no doubt, be more vigilant as to what frequency gets set in the radio. But some low hanging fruit of aviation safety resides in the chart below that could almost entirely eliminate these types of problems. Put the ground control frequencies where pilots are looking -- near the runways where they get off.

Being more clear will allow fewer mistakes and require less head-down time during taxi.

 

New.

 

Louisville SDF

Consider the following taxi instruction from the gate (where "HS4" text is) to runway 35R. "Southwest 1 taxi Mike, Gulf, Delta hold short of Fox, cross runway 29".

 

Original

 

New.

 

Benefits: Taxiways are much easier to find and follow. Tower and ground frequencies are easy to find. Relevant maximum sizes for taxiways are rapidly found or, just as important, rightfully ignored.

 

Taxiway Design Principles
Design principles for readable taxiway markings.

1. Whenever it improves clarity, the letters themselves should indicate the direction of the taxiway by their alignment. In some cases having letters at the same angle as the taxiway they're on improves recognition. Letters should be as evenly spaced as possible--humans pick up quickly on patterns.

2. The letter should be on the taxiway as much as possible. It's too easy to confuse one with another when they are off to the side, primarily when other taxiways are nearby.

3. Letters should be near intersections so your eye doesn't have to travel far to see what the intersecting taxiway is.

4. You should not have to hunt for a taxiway designator when clearing any runway. They should be obvious and large.

5. Make the taxiway letters larger. They are the most important element, we should be able to see them clearly and quickly. Seeing the designators is much more important than seeing the roadways that surround the airport.

6. Carefully vary text sizes: Main taxiways with larger letters and short taxiways with smaller letters can improve clarity. Consistency is important. If a taxiway is to have bigger letters ALL the letters for that taxiway should have the bigger letters if possible.

7. Put the tower frequency for runway right on the black using inverted colors. Pilots shouldn't have to be searching the top bar for these frequencies, there's simply no need.

8. Put the ground control frequencies in light gray next to the runways since pilots will already be looking there. Yes, we NORMALLY preselect these but changes happen and pilots forget.

All these principles must be applied by a good human eyeball that can put them to good use and is interested in one goal: clarity.


© 2016 Jeff Goin & Tim Kaiser   Remember: If there's air there, it should be flown in!