TRACON flm providing a skill check described a loss of separation event when a second departure over...

Narrative:

I was the flm performing a skill check on a developmental. We had just taken the position and had a few traffic situations that he had fallen behind on. Aircraft X; a runway xx departure; was climbing on a vector/classic SID. Air carrier Y was a [runway] yyr departure that was on a RNAV SID. Both aircraft meet at a way point called zzzzz. Air carrier Y was overtaking aircraft X. Aircraft X was turned eastbound; climbed; and [then] stopped once we realized the overtake. Traffic was called to the trailing aircraft; air carrier Y; but he was already above aircraft X and he couldn't see him. Loss of separation occurred. In addition; the trainee told air carrier Y to climb via the SID; which means to cross zzzzz below 7;000 ft. Air carrier Y stated; 'roger; cleared unrestricted to FL190.' trainee did not catch the read back error; nor did I. We had a couple of difficult situations that we were dealing with at the time. Had air carrier Y stopped the climb at 7;000 ft; there would have been no loss of separation. I feel that these 'climb via' on the RNAV sids cause more confusion. Some aircraft are climbing to 7;000 ft only and some are climbing via the SID; this is confusing. If all aircraft came off climbing to the same altitude and let the departure controller climb them; traffic permitting; this [might] not have happened. Most of the pilots are extremely confused on these 'climb via' sids.

Original NASA ASRS Text

Title: TRACON FLM providing a skill check described a loss of separation event when a second departure overtook a preceding aircraft; the reporter listing both a failed hear back error and confused 'climb via' procedure/s as causal factors.

Narrative: I was the FLM performing a skill check on a developmental. We had just taken the position and had a few traffic situations that he had fallen behind on. Aircraft X; a Runway XX departure; was climbing on a vector/classic SID. Air Carrier Y was a [Runway] YYR departure that was on a RNAV SID. Both aircraft meet at a way point called ZZZZZ. Air Carrier Y was overtaking Aircraft X. Aircraft X was turned eastbound; climbed; and [then] stopped once we realized the overtake. Traffic was called to the trailing aircraft; Air Carrier Y; but he was already above Aircraft X and he couldn't see him. Loss of separation occurred. In addition; the trainee told Air Carrier Y to climb via the SID; which means to cross ZZZZZ below 7;000 FT. Air Carrier Y stated; 'Roger; cleared unrestricted to FL190.' Trainee did not catch the read back error; nor did I. We had a couple of difficult situations that we were dealing with at the time. Had Air Carrier Y stopped the climb at 7;000 FT; there would have been no loss of separation. I feel that these 'climb via' on the RNAV SIDs cause more confusion. Some aircraft are climbing to 7;000 FT only and some are climbing via the SID; this is confusing. If all aircraft came off climbing to the same altitude and let the Departure Controller climb them; traffic permitting; this [might] not have happened. Most of the pilots are extremely confused on these 'climb via' SIDs.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	956532
Time
Date	201106
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Daylight
Aircraft 1
Make Model Name	Citation I (C500)
Operating Under FAR Part	Part 91
Flight Phase	Climb
Route In Use	Vectors SID ZZZ
Aircraft 2
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Climb
Route In Use	SID ZZZ RNAV
Flight Plan	IFR
Person 1
Function	Approach Departure
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types Conflict Airborne Conflict Deviation - Altitude Overshoot Deviation - Procedural Clearance Deviation - Procedural Published Material / Policy

TRACON flm providing a skill check described a loss of separation event when a second departure overtook a preceding aircraft; the reporter listing both a failed hear back error and confused 'climb via' procedure/s as causal factors.