Narrative:

A meeting was taking place; such that staffing of our tower cabin attendant had to be decreased for a couple hours. Therefore; management assigned a support specialist to fill in during this period. I was working local control. Traffic was extremely light. Ground control just got relieved by the support specialist. There were absolutely no aircraft movements taking place on our surface area at that time. The support specialist was seated at the ground control position. I do not write about this event to highlight this person's lack of situational awareness. I write this to provide an example as to how excessive our obstructed visibility is from our tower cabin attendant. I also write to demonstrate how precious seconds can elapse when a controller is caught off guard. Had this controller been able to simply turn his head to scan our movement areas (rather than walking from one side of the tower cabin attendant to the other); he likely would've made the correlation that the initial call was from the aircraft that had just landed. In the summer of 2003; before we moved to our new tower; it became evident just how enormous our obstruction to visibility had become. The computer simulation showed virtually no obstruction. In real life; the obstruction to vision was enormous. There was considerable controversy about this. All the controllers clamored that the floor be raised to improve visibility. A july 2003 memo from the regional office arrived. It put an end to the thought of a raised floor being constructed. Part of that memo stated...over the past few years we have learned that the physical location of position of operation are critical in the new higher and larger area cabs that are being built. As the towers go up in ht and the square footage increases; the shadow area directly below the facility gets larger. This fact combined with the closeness of your 2 parallel runways makes this situation even more critical. The original replacement of your local control position at the east and west sides of the new tower create blind spots on one or both runways when viewed from those position. By relocating the local and ground position to the north and south sides of the tower cabin attendant you will eliminate the look down problem and have a clear view of the movement areas. Although other options were reviewed such as raising the cabin attendant floor and creating an operating position on a raised area in the center of the cabin attendant; it was determined that they could create more problems than they would solve. Focusing on an operating environment to accommodate a single local and ground position with an unobstructed view is not acceptable. Visibility is obstructed; even for our tallest controllers. An inexpensive accommodation was made by providing risers that could be stood upon to see out the windows from the designated operating position. However; management does not require that controllers use the risers. When a situation develops that requires a controller to be able to scan both sides of our airport nearly simultaneously; it will be physically impossible for the controller to do so.

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Original NASA ASRS Text

Title: CMH CTLR EXPRESSED CONCERN REGARDING VISIBILITY LIMITATIONS IN THE TWR CAB.

Narrative: A MEETING WAS TAKING PLACE; SUCH THAT STAFFING OF OUR TWR CAB HAD TO BE DECREASED FOR A COUPLE HRS. THEREFORE; MGMNT ASSIGNED A SUPPORT SPECIALIST TO FILL IN DURING THIS PERIOD. I WAS WORKING LCL CTL. TFC WAS EXTREMELY LIGHT. GND CTL JUST GOT RELIEVED BY THE SUPPORT SPECIALIST. THERE WERE ABSOLUTELY NO ACFT MOVEMENTS TAKING PLACE ON OUR SURFACE AREA AT THAT TIME. THE SUPPORT SPECIALIST WAS SEATED AT THE GND CTL POS. I DO NOT WRITE ABOUT THIS EVENT TO HIGHLIGHT THIS PERSON'S LACK OF SITUATIONAL AWARENESS. I WRITE THIS TO PROVIDE AN EXAMPLE AS TO HOW EXCESSIVE OUR OBSTRUCTED VISIBILITY IS FROM OUR TWR CAB. I ALSO WRITE TO DEMONSTRATE HOW PRECIOUS SECONDS CAN ELAPSE WHEN A CTLR IS CAUGHT OFF GUARD. HAD THIS CTLR BEEN ABLE TO SIMPLY TURN HIS HEAD TO SCAN OUR MOVEMENT AREAS (RATHER THAN WALKING FROM ONE SIDE OF THE TWR CAB TO THE OTHER); HE LIKELY WOULD'VE MADE THE CORRELATION THAT THE INITIAL CALL WAS FROM THE ACFT THAT HAD JUST LANDED. IN THE SUMMER OF 2003; BEFORE WE MOVED TO OUR NEW TWR; IT BECAME EVIDENT JUST HOW ENORMOUS OUR OBSTRUCTION TO VISIBILITY HAD BECOME. THE COMPUTER SIMULATION SHOWED VIRTUALLY NO OBSTRUCTION. IN REAL LIFE; THE OBSTRUCTION TO VISION WAS ENORMOUS. THERE WAS CONSIDERABLE CONTROVERSY ABOUT THIS. ALL THE CTLRS CLAMORED THAT THE FLOOR BE RAISED TO IMPROVE VISIBILITY. A JULY 2003 MEMO FROM THE REGIONAL OFFICE ARRIVED. IT PUT AN END TO THE THOUGHT OF A RAISED FLOOR BEING CONSTRUCTED. PART OF THAT MEMO STATED...OVER THE PAST FEW YEARS WE HAVE LEARNED THAT THE PHYSICAL LOCATION OF POS OF OP ARE CRITICAL IN THE NEW HIGHER AND LARGER AREA CABS THAT ARE BEING BUILT. AS THE TWRS GO UP IN HT AND THE SQUARE FOOTAGE INCREASES; THE SHADOW AREA DIRECTLY BELOW THE FACILITY GETS LARGER. THIS FACT COMBINED WITH THE CLOSENESS OF YOUR 2 PARALLEL RWYS MAKES THIS SITUATION EVEN MORE CRITICAL. THE ORIGINAL REPLACEMENT OF YOUR LCL CTL POS AT THE E AND W SIDES OF THE NEW TWR CREATE BLIND SPOTS ON ONE OR BOTH RWYS WHEN VIEWED FROM THOSE POS. BY RELOCATING THE LCL AND GND POS TO THE N AND S SIDES OF THE TWR CAB YOU WILL ELIMINATE THE LOOK DOWN PROB AND HAVE A CLR VIEW OF THE MOVEMENT AREAS. ALTHOUGH OTHER OPTIONS WERE REVIEWED SUCH AS RAISING THE CAB FLOOR AND CREATING AN OPERATING POS ON A RAISED AREA IN THE CTR OF THE CAB; IT WAS DETERMINED THAT THEY COULD CREATE MORE PROBS THAN THEY WOULD SOLVE. FOCUSING ON AN OPERATING ENVIRONMENT TO ACCOMMODATE A SINGLE LCL AND GND POS WITH AN UNOBSTRUCTED VIEW IS NOT ACCEPTABLE. VISIBILITY IS OBSTRUCTED; EVEN FOR OUR TALLEST CTLRS. AN INEXPENSIVE ACCOMMODATION WAS MADE BY PROVIDING RISERS THAT COULD BE STOOD UPON TO SEE OUT THE WINDOWS FROM THE DESIGNATED OPERATING POS. HOWEVER; MGMNT DOES NOT REQUIRE THAT CTLRS USE THE RISERS. WHEN A SITUATION DEVELOPS THAT REQUIRES A CTLR TO BE ABLE TO SCAN BOTH SIDES OF OUR ARPT NEARLY SIMULTANEOUSLY; IT WILL BE PHYSICALLY IMPOSSIBLE FOR THE CTLR TO DO SO.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.