Near midair collision between 2 small transport twins on scenic passenger tour of ground canyon.

Attributes
ACN	283234
Time
Date	199409
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : gcn
State Reference	AZ
Altitude	msl bound lower : 8000 msl bound upper : 9000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : sea
Operator	common carrier : air taxi
Make Model Name	Cessna 402/402C/B379 Businessliner/Utiliner
Operating Under FAR Part	Part 135
Flight Phase	cruise other
Flight Plan	None
Aircraft 2
Operator	common carrier : air taxi
Make Model Name	Cessna 402/402C/B379 Businessliner/Utiliner
Operating Under FAR Part	Part 135
Flight Phase	cruise other
Flight Plan	None
Person 1
Affiliation	company : air taxi
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : cfi pilot : commercial
Experience	flight time last 90 days : 180 flight time total : 1500 flight time type : 200
ASRS Report	283234
Person 2
Affiliation	company : air taxi
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : nmac other anomaly other
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 100 vertical : 500
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

While flying the tour at 8500 ft in the grand canyon over supai point, I was following another company aircraft of the same make and model at a distance 1 mi. The other aircraft made a turn to the south and I lost contact while tending to the tour system in the aircraft. I made my left turn toward the south and continued on the route. I had been looking for the other aircraft ahead of me (as he was ahead during the whole route previously), when I caught a glimpse of something at my 8 O'clock. It was the other aircraft at less than a 1/4 mi and converging at a 45 degree angle with me. I instantly pulled up, climbing 500 ft -- and the other aircraft passed underneath at 100 ft. The other pilot did not see me until crossing under. There were no injuries/no contact, etc. The cause was -- each of us losing the others position and not looking for the other aircraft in an unexpected position. We should maintain contact every 30 seconds or so. We were both flying into the southwest, which didn't help. Also, pilot's aircraft flying in the canyon should have TCASII installed, due to the high volume of aircraft. I and the other pilot discussed the situation thoroughly as I have here and both agree we should not experience it again due to the experience.

Original NASA ASRS Text

Title: NMAC BTWN 2 SMT TWINS ON SCENIC PAX TOUR OF GND CANYON.

Narrative: WHILE FLYING THE TOUR AT 8500 FT IN THE GRAND CANYON OVER SUPAI POINT, I WAS FOLLOWING ANOTHER COMPANY ACFT OF THE SAME MAKE AND MODEL AT A DISTANCE 1 MI. THE OTHER ACFT MADE A TURN TO THE S AND I LOST CONTACT WHILE TENDING TO THE TOUR SYS IN THE ACFT. I MADE MY L TURN TOWARD THE S AND CONTINUED ON THE RTE. I HAD BEEN LOOKING FOR THE OTHER ACFT AHEAD OF ME (AS HE WAS AHEAD DURING THE WHOLE RTE PREVIOUSLY), WHEN I CAUGHT A GLIMPSE OF SOMETHING AT MY 8 O'CLOCK. IT WAS THE OTHER ACFT AT LESS THAN A 1/4 MI AND CONVERGING AT A 45 DEG ANGLE WITH ME. I INSTANTLY PULLED UP, CLBING 500 FT -- AND THE OTHER ACFT PASSED UNDERNEATH AT 100 FT. THE OTHER PLT DID NOT SEE ME UNTIL XING UNDER. THERE WERE NO INJURIES/NO CONTACT, ETC. THE CAUSE WAS -- EACH OF US LOSING THE OTHERS POS AND NOT LOOKING FOR THE OTHER ACFT IN AN UNEXPECTED POS. WE SHOULD MAINTAIN CONTACT EVERY 30 SECONDS OR SO. WE WERE BOTH FLYING INTO THE SW, WHICH DIDN'T HELP. ALSO, PLT'S ACFT FLYING IN THE CANYON SHOULD HAVE TCASII INSTALLED, DUE TO THE HIGH VOLUME OF ACFT. I AND THE OTHER PLT DISCUSSED THE SIT THOROUGHLY AS I HAVE HERE AND BOTH AGREE WE SHOULD NOT EXPERIENCE IT AGAIN DUE TO THE EXPERIENCE.

Data retrieved from NASA's ASRS site as of July 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.