Narrative:

My student and I were practicing landings for an upcoming check ride in a cessna 172. After our touch-and-go; we departed runway 11 for a left traffic pattern. Shortly after departing the runway surface an experimental aircraft announced his departure from runway 11 behind us. Upon reaching 700 ft. AGL (above ground level); about half a mile off the end of the runway; my student began his left turn onto the crosswind leg. Seconds later we hear the experimental make his crosswind call. I could not see the traffic at the time and upon searching the area realized the experimental to be at my 9:00 position. I realized at this time the experimental had began his crosswind turn almost immediately after takeoff for a northbound departure. As my student and I were beginning to prepare for our downwind leg. Another aircraft; a lancair legacy 2000; departed from runway 11. Just as my student completed his turn to downwind the [lancair] announced his turn to crosswind. Seconds later my adb (automatic dependent surveillance) alerted me to traffic at my 10 and same altitude. I caught sight of [lancair] as it passed through the downwind at my altitude from the left to right. The aircraft was within 500 ft. Of our aircraft. Shortly after crossing our path the lancair met up with the experimental aircraft for formation flight departing to the north. Longmont has been plagued with a series of these events. Local pilots of this airport as well as surrounding airports need dire retraining on how to determine the proper traffic pattern direction as well as the proper means for departing the traffic pattern. Careless and reckless flying such as this which results in a near mid-air collision is unacceptable especially in an environment were there is a high volume of traffic as well as a high number of student pilots. Factors such as impatience; or disregard for the published recommendation may have played a cause in both pilots flying the pattern as they did. Regardless; to fly a pattern within other aircraft and to depart the pattern by crossing in front of them is unacceptable.

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Original NASA ASRS Text

Title: C-172 Flight Instructor reported a near mid-air collision with another aircraft while maneuvering in the airport traffic pattern.

Narrative: My student and I were practicing landings for an upcoming check ride in a Cessna 172. After our touch-and-go; we departed Runway 11 for a left traffic pattern. Shortly after departing the runway surface an Experimental aircraft announced his departure from Runway 11 behind us. Upon reaching 700 ft. AGL (Above Ground Level); about half a mile off the end of the runway; my student began his left turn onto the crosswind leg. Seconds later we hear the experimental make his crosswind call. I could not see the traffic at the time and upon searching the area realized the experimental to be at my 9:00 position. I realized at this time the experimental had began his crosswind turn almost immediately after takeoff for a northbound departure. As my student and I were beginning to prepare for our downwind leg. Another aircraft; a Lancair Legacy 2000; departed from Runway 11. Just as my student completed his turn to downwind the [Lancair] announced his turn to crosswind. Seconds later my ADB (Automatic Dependent Surveillance) alerted me to traffic at my 10 and same altitude. I caught sight of [Lancair] as it passed through the downwind at my altitude from the left to right. The aircraft was within 500 ft. of our aircraft. Shortly after crossing our path the Lancair met up with the Experimental aircraft for formation flight departing to the North. Longmont has been plagued with a series of these events. Local pilots of this airport as well as surrounding airports need dire retraining on how to determine the proper traffic pattern direction as well as the proper means for departing the traffic pattern. Careless and reckless flying such as this which results in a near mid-air collision is unacceptable especially in an environment were there is a high volume of traffic as well as a high number of student pilots. Factors such as impatience; or disregard for the published recommendation may have played a cause in both pilots flying the pattern as they did. Regardless; to fly a pattern within other aircraft and to depart the pattern by crossing in front of them is unacceptable.

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.