Narrative:

I am writing this report after being informed by management of a loss (loss of standard separation); after being reported by the pilot of aircraft X. I was training the new flm who is a previously certified radar controller; but has had no tower experience prior to this facility. We had been working aircraft Y in the pattern on runway 24 for several laps; when aircraft X checked on about 10 mi south of the airport on final for runway 34 for a full stop landing. The trainee cleared aircraft X to land when he checked on. At that time aircraft Y was on the crosswind in right traffic for runway 24. Aircraft Y called midfield for runway 24 requesting the option. The trainee cleared aircraft Y for a touch and go on runway 24 and told the pilot that there was aircraft X on an 8 mile final for runway 34. We did not tell aircraft X about aircraft Y. Aircraft Y read back the traffic; but not the touch and go clearance. Neither the trainee nor myself picked up this omission. Aircraft Y turned about a 1 mi final as aircraft X passed inside the outer marker on runway 34; a 3-4 mi final. Aircraft X was traveling at 110 kts according to his data tag. I do not know aircraft Y's exact speed at the time; but I estimated it to be 60-70 kts based on his type of aircraft. Aircraft Y completed his touch and go on runway 24 and had passed through the runway intersection as aircraft X crossed the runway 34 threshold to land.the pilot of aircraft X called the facility 5 days later to report that he saw an aircraft flying through the runway intersection as he was rolling out past taxiway C on runway 34. This is a significant difference than what we witnessed from the tower. I knew that this operation would be close to minimums; but I let the trainee continue without adjusting his plan because I believed that there would be the required separation at the runway. A mor (mandatory occurrence report) was filed after the pilot of aircraft X called; as required by the SOP. I did not file an mor at the time of the event because I did not believe that a loss of runway separation had taken place. The evidence used to declare this event a risk analysis event was aircraft X's report and the projection of the limited radar presentation; since there is no radar coverage at the surface at roa or an asde-X. The instructor pilot of aircraft Y was contacted as part of the fact finding; and stated that he also thought the operation was 'close' but could not say for sure where aircraft X was as he completed his touch and go. He also said that he would not have hesitated to contact the facility if he felt that he had been in an unsafe situation. On another note - I am very frustrated at this process. The testimony of the pilot of aircraft X (given almost 1 week later); and the limited/inaccurate radar display seem to be deemed more reliable evidence than that of the tower controllers. I feel like the event was decided to be a loss before the testimony of myself and my trainee were even gathered. And the pilot of aircraft Y and controller in charge in the tower at the time were never even interviewed. The only recommendation I have is to install an asde-X at roa to be able to say for sure whether this was a loss of runway separation. The use of the limited radar presentation to project the aircraft's position on the ground is an unacceptably inaccurate way of proving a safe of unsafe operation. A projection of the radar does not show the changing speeds of the aircraft over the runway environment easily observed by the naked eye. An asde-X would have fewer gaps in coverage and be able to 'see' an aircraft as it does a touch and go or slows on their landing rollout more accurately. I believe that there was no loss of runway separation. The pilot of aircraft Y did not believe that separation was lost; but aircraft X did. Since separation was at a minimum and the limited radar replay available is so imprecise; there is no way to prove that separation was not lost.

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Original NASA ASRS Text

Title: Roanoke Tower Instructor reported of a loss of separation reported by a pilot a week after the incident. The Controller advised the aircraft was through the crossing intersection before the landing aircraft was at the runway threshold.

Narrative: I am writing this report after being informed by management of a LoSS (Loss of Standard Separation); after being reported by the pilot of Aircraft X. I was training the new FLM who is a previously certified radar controller; but has had no tower experience prior to this facility. We had been working Aircraft Y in the pattern on RWY 24 for several laps; when Aircraft X checked on about 10 mi south of the airport on final for RWY 34 for a full stop landing. The trainee cleared Aircraft X to land when he checked on. At that time Aircraft Y was on the crosswind in right traffic for RWY 24. Aircraft Y called midfield for RWY 24 requesting the option. The trainee cleared Aircraft Y for a touch and go on RWY 24 and told the pilot that there was Aircraft X on an 8 mile final for RWY 34. We did not tell Aircraft X about Aircraft Y. Aircraft Y read back the traffic; but not the touch and go clearance. Neither the trainee nor myself picked up this omission. Aircraft Y turned about a 1 mi final as Aircraft X passed inside the outer marker on RWY 34; a 3-4 mi final. Aircraft X was traveling at 110 kts according to his data tag. I do not know Aircraft Y's exact speed at the time; but I estimated it to be 60-70 kts based on his type of aircraft. Aircraft Y completed his touch and go on RWY 24 and had passed through the runway intersection as Aircraft X crossed the RWY 34 threshold to land.The pilot of Aircraft X called the facility 5 days later to report that he saw an aircraft flying through the runway intersection as he was rolling out past Taxiway C on RWY 34. This is a significant difference than what we witnessed from the tower. I knew that this operation would be close to minimums; but I let the trainee continue without adjusting his plan because I believed that there would be the required separation at the runway. A MOR (Mandatory Occurrence Report) was filed after the pilot of Aircraft X called; as required by the SOP. I did not file an MOR at the time of the event because I did not believe that a loss of runway separation had taken place. The evidence used to declare this event a risk analysis event was Aircraft X's report and the projection of the limited radar presentation; since there is no radar coverage at the surface at ROA or an ASDE-X. The instructor pilot of Aircraft Y was contacted as part of the fact finding; and stated that he also thought the operation was 'close' but could not say for sure where Aircraft X was as he completed his touch and go. He also said that he would not have hesitated to contact the facility if he felt that he had been in an unsafe situation. On another note - I am very frustrated at this process. The testimony of the pilot of Aircraft X (given almost 1 week later); and the limited/inaccurate radar display seem to be deemed more reliable evidence than that of the tower controllers. I feel like the event was decided to be a LoSS before the testimony of myself and my trainee were even gathered. And the pilot of Aircraft Y and CIC in the tower at the time were never even interviewed. The only recommendation I have is to install an ASDE-X at ROA to be able to say for sure whether this was a loss of runway separation. The use of the limited radar presentation to project the aircraft's position on the ground is an unacceptably inaccurate way of proving a safe of unsafe operation. A projection of the radar does not show the changing speeds of the aircraft over the runway environment easily observed by the naked eye. An ASDE-X would have fewer gaps in coverage and be able to 'see' an aircraft as it does a touch and go or slows on their landing rollout more accurately. I believe that there was no loss of runway separation. The pilot of Aircraft Y did not believe that separation was lost; but Aircraft X did. Since separation was at a minimum and the limited radar replay available is so imprecise; there is no way to prove that separation was not lost.

Data retrieved from NASA's ASRS site 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.