A C172 instructor pilot reported that during his student's first solo flight; visibility decreased e...

Narrative:

At xa:30 my student met me at ZZZ. We conducted preflight inspection of a cessna 172; that included a pilot safety briefing and a weather check on fore flight. We flew to ZZZ1 airport from ZZZ; where we conducted 4 landings before taxing to the ramp to allow me to sign endorsements for her first solo flight.the weather was VFR; but visibility was not more than 10 miles. I gave her last minute safety instructions and told her; if the visibility made it so she was unable to land at ZZZ1 to contact ATC tower at ZZZ and to land there. I didn't expect the visibly to become worse; but the visibly was not the typical 50 miles that day. I endorsed my student to conduct solo flight. She departed runway 33 from ZZZ1 to the north at xb:30 in a C172SP model cessna. I watched her turn crosswind; downwind; base; and then lost sight of her before she turned onto final for runway 33 at ZZZ1. I expected that she was able to see through the mist and expected to see her to come through; but she did not.I immediately contacted her on her cell phone. She informed me that she lost sight of the airport turning from base to final. I told her to climb to 7;500 feet and to contact ZZZ tower to land there. She was composed and said that she was above the clouds. (I found out months later that she had been engulfed in low level ground fog and just climbed out of it before I called her.) she contacted ZZZ tower; and was told that ZZZ was IFR and that she would not be able to land there.an unexpected layer of ground fog rolled into the area with 300 foot ceilings. ZZZ tower determined the safest airport not affected by the fog was at ZZZ2. She was instructed to contact center for flight following. She had conducted practice landings at ZZZ2; ZZZ; and at ZZZ1 prior to conducting this flight. After I knew she was enroute to ZZZ2; I made my way to ZZZ2; and contacted ZZZ2 tower. I was told that my student's aircraft was on a 1 mile short final and I asked ZZZ2 tower to call me when she landed safely. ZZZ2 tower contacted me to let me know she had landed safely a few minutes later. My student contacted me to tell me she landed safely at ZZZ2 as well. She sounded calm and in control. I told her that her parents and I were 45 minutes away; and that if she felt up to that she could finish her solo with 2 more landings. She conducted two additional landings to complete her solo flight prerequisites.ATC personnel at ZZZ said that they and controllers at center said that she did a great job remaining composed; and were happy to hear she succeeded in her flight and that she had arrived safely.corrective actions - unexpected weather does occur; but the visibility was not the greatest. Metar weather and forecast weather that morning said VFR and was expected to remain VFR for the day. After the ground fog rolled in; ZZZ remained low IFR until xg:00. Maybe I could have looked at the radar picture again right after we finished 4 touch and goes and before I sent her on her first solo flight ten minutes later. Maybe a 10 mile visibility or greater is warranted to conduct flight for a solo student. Having a hand held radio to contact a solo student would have been worth having instead of relying on cell communications.

Original NASA ASRS Text

Title: A C172 instructor pilot reported that during his student's first solo flight; visibility decreased enough after that ATC assistance was sought to locate and navigate to a nearby Class D airport.

Narrative: At XA:30 my student met me at ZZZ. We conducted preflight inspection of a Cessna 172; that included a pilot safety briefing and a weather check on fore flight. We flew to ZZZ1 Airport from ZZZ; where we conducted 4 landings before taxing to the ramp to allow me to sign endorsements for her first solo flight.The weather was VFR; but visibility was not more than 10 miles. I gave her last minute safety instructions and told her; if the visibility made it so she was unable to land at ZZZ1 to contact ATC Tower at ZZZ and to land there. I didn't expect the visibly to become worse; but the visibly was not the typical 50 miles that day. I endorsed my student to conduct solo flight. She departed Runway 33 from ZZZ1 to the north at XB:30 in a C172SP model Cessna. I watched her turn crosswind; downwind; base; and then lost sight of her before she turned onto final for Runway 33 at ZZZ1. I expected that she was able to see through the mist and expected to see her to come through; but she did not.I immediately contacted her on her cell phone. She informed me that she lost sight of the airport turning from base to final. I told her to climb to 7;500 feet and to contact ZZZ Tower to land there. She was composed and said that she was above the clouds. (I found out months later that she had been engulfed in low level ground fog and just climbed out of it before I called her.) She contacted ZZZ Tower; and was told that ZZZ was IFR and that she would not be able to land there.An unexpected layer of ground fog rolled into the area with 300 foot ceilings. ZZZ Tower determined the safest Airport not affected by the fog was at ZZZ2. She was instructed to contact Center for flight following. She had conducted practice landings at ZZZ2; ZZZ; and at ZZZ1 prior to conducting this flight. After I knew she was enroute to ZZZ2; I made my way to ZZZ2; and contacted ZZZ2 Tower. I was told that my student's aircraft was on a 1 mile short final and I asked ZZZ2 Tower to call me when she landed safely. ZZZ2 Tower contacted me to let me know she had landed safely a few minutes later. My student contacted me to tell me she landed safely at ZZZ2 as well. She sounded calm and in control. I told her that her parents and I were 45 minutes away; and that if she felt up to that she could finish her solo with 2 more landings. She conducted two additional landings to complete her solo flight prerequisites.ATC personnel at ZZZ said that they and controllers at Center said that she did a great job remaining composed; and were happy to hear she succeeded in her flight and that she had arrived safely.Corrective actions - unexpected weather does occur; but the visibility was not the greatest. METAR weather and forecast weather that morning said VFR and was expected to remain VFR for the day. After the ground fog rolled in; ZZZ remained low IFR until XG:00. Maybe I could have looked at the radar picture again right after we finished 4 touch and goes and before I sent her on her first solo flight ten minutes later. Maybe a 10 mile visibility or greater is warranted to conduct flight for a solo student. Having a hand held radio to contact a solo student would have been worth having instead of relying on cell communications.

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.

Attributes
ACN	1397450
Time
Date	201608
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	Final Approach
Route In Use	Visual Approach
Flight Plan	None
Person 1
Function	Pilot Not Flying Instructor
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Commercial Flight Crew Flight Instructor
Experience	Flight Crew Last 90 Days 100 Flight Crew Total 612 Flight Crew Type 200
Events
Anomaly	Deviation - Procedural FAR Inflight Event / Encounter VFR In IMC

A C172 instructor pilot reported that during his student's first solo flight; visibility decreased enough after that ATC assistance was sought to locate and navigate to a nearby class D airport.