Small aircraft twin landed on runway less than 2000' behind another small aircraft twin.

Attributes
ACN	131284
Time
Date	198912
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : prc
State Reference	AZ
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : instructional
Make Model Name	Small Aircraft, Low Wing, 2 Eng, Retractable Gear
Flight Phase	landing : go around landing other
Flight Plan	None
Aircraft 2
Operator	general aviation : instructional
Make Model Name	Small Aircraft, Low Wing, 2 Eng, Retractable Gear
Flight Phase	landing : go around landing other
Flight Plan	None
Person 1
Affiliation	government : faa
Function	controller : local
Qualification	pilot : atp
Experience	controller non radar : 2 controller radar : 2 flight time total : 6000
ASRS Report	131284
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : student
Events
Anomaly	conflict : ground less severe non adherence : required legal separation
Independent Detector	other controllera
Resolutory Action	none taken : insufficient time
Consequence	faa : reviewed incident with flight crew faa : investigated Other
Miss Distance	horizontal : 2000
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Deviation

Narrative:

I lost runway separation between 2 twin engine aircraft on runway 29. The second twin landed with less than 2000' separation behind the first that was still on the runway. I was extremely busy with 8 aircraft in the pattern for touch and goes. The traffic pattern was extended and it was extremely difficult to see my traffic to sequence them without radar. In addition the frequency congestion was extremely bad and I had to repeat most of my instructions two, three times. I had an additional 5 aircraft inbound to the airport at the time. This was an extremely high workload as I had a very difficult time seeing the inbnds to safely sequence them into the traffic pattern. Additionally many of my xmissions were blocked by two aircraft requesting services on VFR practice apches to the airport. The frequency was blocked when I tried to send the twin around. I attempted to instruct aircraft to remain outside the air traffic area. However many continued inbound anyway. Either from not receiving my denial due to frequency congestion or poor pilot technique. I also instructed many of the aircraft to make full stop lndgs and taxi back. Again most continued to make touch and goes and to remain in the pattern. I told the practice approach aircraft 'unable' to their request but they took valuable frequency time to tell me a lengthy monologue of what they were going to do anyway. Corrective actions: install radar to help reduce the workload. Build an additional runway to accommodate the large request for touch and goes here. Instruct management to encourage controllers to limit the amount of traffic here until these items are provided. Instead now management encourages controllers to 'build up the count'. This causes less experienced controllers to feel pressure to take on more aircraft than they can safely handle. Management should set strict guidelines for controllers on what services to provide VFR practice apches, and inform the users of that.

Original NASA ASRS Text

Title: SMA TWIN LANDED ON RWY LESS THAN 2000' BEHIND ANOTHER SMA TWIN.

Narrative: I LOST RWY SEPARATION BETWEEN 2 TWIN ENGINE ACFT ON RWY 29. THE SECOND TWIN LANDED WITH LESS THAN 2000' SEPARATION BEHIND THE FIRST THAT WAS STILL ON THE RWY. I WAS EXTREMELY BUSY WITH 8 ACFT IN THE PATTERN FOR TOUCH AND GOES. THE TFC PATTERN WAS EXTENDED AND IT WAS EXTREMELY DIFFICULT TO SEE MY TFC TO SEQUENCE THEM WITHOUT RADAR. IN ADDITION THE FREQ CONGESTION WAS EXTREMELY BAD AND I HAD TO REPEAT MOST OF MY INSTRUCTIONS TWO, THREE TIMES. I HAD AN ADDITIONAL 5 ACFT INBND TO THE ARPT AT THE TIME. THIS WAS AN EXTREMELY HIGH WORKLOAD AS I HAD A VERY DIFFICULT TIME SEEING THE INBNDS TO SAFELY SEQUENCE THEM INTO THE TFC PATTERN. ADDITIONALLY MANY OF MY XMISSIONS WERE BLOCKED BY TWO ACFT REQUESTING SERVICES ON VFR PRACTICE APCHES TO THE ARPT. THE FREQ WAS BLOCKED WHEN I TRIED TO SEND THE TWIN AROUND. I ATTEMPTED TO INSTRUCT ACFT TO REMAIN OUTSIDE THE ATA. HOWEVER MANY CONTINUED INBND ANYWAY. EITHER FROM NOT RECEIVING MY DENIAL DUE TO FREQ CONGESTION OR POOR PLT TECHNIQUE. I ALSO INSTRUCTED MANY OF THE ACFT TO MAKE FULL STOP LNDGS AND TAXI BACK. AGAIN MOST CONTINUED TO MAKE TOUCH AND GOES AND TO REMAIN IN THE PATTERN. I TOLD THE PRACTICE APCH ACFT 'UNABLE' TO THEIR REQUEST BUT THEY TOOK VALUABLE FREQ TIME TO TELL ME A LENGTHY MONOLOGUE OF WHAT THEY WERE GOING TO DO ANYWAY. CORRECTIVE ACTIONS: INSTALL RADAR TO HELP REDUCE THE WORKLOAD. BUILD AN ADDITIONAL RWY TO ACCOMMODATE THE LARGE REQUEST FOR TOUCH AND GOES HERE. INSTRUCT MGMNT TO ENCOURAGE CTLRS TO LIMIT THE AMOUNT OF TFC HERE UNTIL THESE ITEMS ARE PROVIDED. INSTEAD NOW MGMNT ENCOURAGES CTLRS TO 'BUILD UP THE COUNT'. THIS CAUSES LESS EXPERIENCED CTLRS TO FEEL PRESSURE TO TAKE ON MORE ACFT THAN THEY CAN SAFELY HANDLE. MGMNT SHOULD SET STRICT GUIDELINES FOR CTLRS ON WHAT SERVICES TO PROVIDE VFR PRACTICE APCHES, AND INFORM THE USERS OF THAT.

Data retrieved from NASA's ASRS site as of August 2007 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.