Amy Gubser, Sarah Roberts, Kirk McKinney - Round-Trip Angel Island

Clockwise loop around Angel Island from Aquatic Park

16.1 km (10.0 miles)

6 hours, 2 minutes on 13 August 2020

Observed and documented by Evan Morrison


Name Gender Age Nation Resides
Amy Appelhans Gubser female 52 United States Pacifica, Calif.
Sarah Roberts female 36-37 United States Redwood City, Calif.
Kirk McKinney male 54 United States Pacifica, Calif.

Support Personnel

  • Greg Gubser - pilot
  • David Roberts - crew
  • Miguel Melendez - kayaker
  • Evan Morrison - observer / documentation

Escort Vessel: Mako (Oyster Point Marina)

Swim Parameters

  • Category: Triple tandem solo, nonstop, unassisted.
  • Rules: MSF Rules of Marathon Swimming, without exception or modification.
  • Equipment used: All three swimmers: textile swimsuit, silicone or latex cap, goggles.

Route Definition

Start @ Aquatic Park beach just west of Dolphin Club dock, exit through Aquatic Park opening, clockwise around Angel Island, return to Aquatic Park beach via Opening.

  • Body of Water: San Francisco Bay
  • Route Type: island loop
  • Start & Finish Location: Aquatic Park beach, just west of Dolphin Club dock. (37.808074, -122.42165)
  • Minimum Route Distance: 16.1 km (10.0 miles) (map).


LongSwimsDB: Round-Trip Angel Island

Swim Data

  • Start: 13 August 2020, 03:19:46 (America/Los_Angeles, UTC-7).
  • Finish: 13 August 2020, 09:22:30
  • Elapsed: 6 hours, 2 minutes, 44 seconds.

Summary of Conditions

Feature Min Max
Water Temp (F) 60 61
Air Temp (F) 54 55
Wind (Beaufort) F0 F2

GPS Track

Trackpoint frequency: 10 minutes. Download raw data (CSV).

Speed Plot

Nutrition: Misc carb drinks, every 30 minutes from kayak.

Observer Report

by Evan Morrison

On Thursday, August 13, 2020, Amy Gubser, Sarah Roberts, and Kirk McKinney completed a triple-tandem solo swim of the Round-Trip Angel Island route in San Francisco Bay: from Aquatic Park beach, through the Opening, past the west end of Alcatraz, around Angel Island clockwise, and returning to Aquatic Park via the east end of Alcatraz and the Opening. On a very favorable day for a RTAI - a mild 1.2-knot max flood, sub-5 knot winds, and 60-61F water, “Mongo and the Mermaids” completed the island loop in 6 hours, 2 minutes, 44 seconds.

Out of caution for the ongoing COVID-19 pandemic, the swim was organized “within the family” – three swimmers who train together, a kayaker who often pilots them, and a captain and crew chief who are spouses of two of the swimmers. The swimmers arrived and exited via Aquatic Park beach and were never on the boat. The captain, crew chief, and observer maintained safe physical distance at all times aboard the open-air boat.

The swimmers and kayaker entered the water just west of the Dolphin Club dock at 3:19am (1 hour, 40 minutes before slack tide at the Golden Gate entrance). RTAI alumna Robin Rose observed the start and texted the time to Evan on the boat. At 3:27 the swimmers linked up with Mako at the Opening. Greg set a course for Point Stuart and the swimmers settled in on starboard.

0350. 60F water, 55F air, Force 2 west wind. Stroke rates: Amy 64, Sarah 53, Kirk 54. We are almost clear of the south shipping channel and will pass to the west of Alcatraz shortly.

0420. First feed. Glovis Stella tanker ship (200 x 35m) is heading out the GG via deepwater channel, but will pass safely to our north. Greg is in contact with VTS. Shooting stars over Sausalito.

Glovis Stella, 4:26am.

0450. Wind laying down (F1) as we enter the lee provided by the Marin headlands. 1 statute mile SE of Pt Stuart. Water temp 60F.

0520. 2 hours elapsed. In the Raccoon Strait - getting a decent push from the flood. Feed between Points Stuart and Lone. A hint of light over the East Bay hills.

Raccoon Strait, 5:18am.

0545. Point Campbell - top o’ the island and halfway. Stroke rates: Amy 65, Sarah 51, Kirk 58. Air temp 54F, wind Force 0 (glass). Ahead of schedule!

0620. 3 hours elapsed. Passing Pt Simpton. Water temp 61F, wind F0. Swimmers in fine spirits as the greet the gorgeous day and ideal conditions.

Between Pt Campbell and Pt Simpton, 5:52am.

0640. A slight headwind arises as we round Quarry Point. Stroke rates: Amy 64, Sarah 51, Kirk 58.

0700. Passing Pt Blunt, entering the deepwater channel. Wind F2. Feed @ 650 allows Kirk to catch up.

0720. Jumping thresher sharks! Wind F3 west. Air temp 55F.

0750. Leisurely feed in middle of deepwater channel. Tugboat passes a few hundred yards to our south, heading out the GG. We are holding the nav-line quite well - very little cross-current. Water temp 60F, air 56F.

0830. Passing east end of Alcatraz. A spectacular sunny morning on the Bay; wind remains muted, F2. Stroke rates: Amy 62, Sarah 51, Kirk 54.

0900. Approaching city-front, just off the Jeremiah O’Brien. All that remains are a routine traverse along the outside of the Hyde Street marina breakwater, then a cool-down lap into the beach. Water temp 61F, air 62F.

092230. Swimmers clear the water on Aquatic Park beach, just west of Dolphin Club dock. Deputy observer Robin Rose texts the finish time to Evan at the Opening. Final elapsed time 6 hours, 2 minutes, 44 seconds.


Additional Photos

Click to enlarge.

Swimmers’ Statement

What inspired you to do this swim?

Amy and Kirk had been training together over summer 2020 and wanted to do a longer swim outside of the usual Aquatic Park-area territory. Neither of them had done RTAI before so this seemed like a good box to tick. Sarah had done RTAI the previous year and was a late addition to the tandem, because the more the merrier!

Describe how you planned for the swim.

We looked at the tide book and saw the morning of August 13 had a fairly mellow tidal swing. We called up Capt. Brent and set it up. Out of respect for the COVID situation, we brought a minimal, local crew - David Roberts (boat), Miguel Melendez (kayak), with Evan Morrison observing. There was plenty of space on the boat for physical distancing.

How did the swim go, generally? Did you face any unanticipated challenges?

The swim went about as well as it possibly could, with near-perfect conditions, good timing with the tides, and no interference from shipping traffic. All of the swimmers were experienced swimming together and had little trouble staying in tandem.


Weather Data

Via NOAA Station FTPC1 - Fort Point, San Francisco, CA

Water Temperature


Air Temperature


Wind Speed

(gust = dotted line)