Date: 201308
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Skyhawk 172/Cutlass 172
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Cruise
Airspace: Class D ZZZ
ATC / advisory: Center ZZZ
Second aircraft: B737 Undifferentiated or Other Model
Reporter organization: Personal
Reporter function: Pilot Flying
Reporter qualification: Flight Crew Private
Human factors: Communication Breakdown; Distraction; Training / Qualification
Anomaly: Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Other / Unknown
Detector: Automation Aircraft RA; Person Air Traffic Control; Person Flight Crew
When detected: In-flight
Result: Flight Crew Took Evasive Action
Contributing factors: Procedure; Manuals; Environment - Non Weather Related
Primary problem: Ambiguous

Narrative: Our aircraft was cruising at 10;500 FT; flying GPS direct. I was the pilot-in-command and was training in simulated instrument conditions under a view-limiting device from the right seat; my brother was acting as safety pilot from the left seat. We were on a VFR flight plan and had been receiving flight following since takeoff. At approximately T-4 minutes we 'requested' a descent from ATC to 8;500 FT and were told to 'maintain VFR.' The autopilot was engaged in 'Nav' mode but was not controlling altitude. At approximately T-1 minutes; we received a traffic advisory from ATC; notifying us of a B737 at our 1-o-clock. We responded 'we're looking.' The 737 received an advisory as well - he was told that we were in a 'VFR descent.' Shortly after receiving the advisory; my brother shouted 'break right! break right!' I removed my view limiting device and saw the 737 much; much closer than it should have been - we later estimated 1;500-2;000 FT; though this is a rough guess. I immediately disconnected the AP and took evasive action by banking sharply to the right. The 737 appeared to take evasive action as well. A collision would have occurred had neither aircraft taken evasive action. ATC called the jet to provide more information; the jet responded that he had been forced to comply with a TCAS RA (the RA audio could be heard in the background). We were both very shaken up. I called on the radio 'Sorry about that... we had you... Cessna XX;' somehow thinking that I was at fault for the incident. We did have him; though not until just before collision was imminent and evasive action was required.A few things contributed to this incident. One major factor was our failure to see and avoid the 737 earlier. Conducting simulated instrument training leads to a sense of complacency in this regard; having no control over the aircraft made the safety pilot feel like a passenger; despite the fact that he was responsible for see-and-avoid. Another major factor was ATC's failure to provide earlier guidance and/or a safety advisory. The Controller did not sound busy; I don't recall her being in control of other aircraft; and the advisory we received sounded casual and routine. I routinely receive VFR vectoring in uncontrolled airspace to avoid IFR traffic; that would have been very useful in this situation. We discussed whether to report a near-miss and decided that the RA report would be sufficient. A later discussion with the Center Watch Controller revealed that the air carrier pilots had us in sight before the RA; we therefore don't know if they were worried about a collision or not. Lessons learned: A safety pilot must take his responsibility to see-and-avoid traffic just as seriously; if not more so; than as if he were the pilot. Using VFR flight following as an alternative to scanning/see-and-avoid could be a deadly mistake. You can't rely on ATC for traffic guidance under VFR; that advisory may never come; and it doesn't legally have to. - TCAS saves lives.




Synopsis: A C-172 pilot conducting under the hood instrument training with a safety observer took evasive action from a descending air carrier aircraft which was responding to a TCAS RA.