Ian's Flight in Chile

Flying down the freeway after take-off. The lower western ridge of Cerro Manquehue is at the top of the picture.
An average climb rate of 4.9m/s or about 1,000 ft per min.
About an hour into the flight we passed this blue lake in forbidding terrain.
We passed over a very deep valley where the road to Argentina goes up to the mountain pass.
Laguna Cuadrada only approximates a square and was still partially frozen over.
On return, overhead the Vitacura airport alongside and to left of the Costanera Norte freeway at mid right. Lucy’s apartment is located at the left upper side of the picture in the semi circular complex.
A “selfie” with Rodrigo post flight.
Where we went – from the OLC GPS trace.

By Ian Cohn, 8 November 2013

Well. Today is the day. Rodrigo Lavanderos, Operations Manager of the Club de Planeadores de Vitacura, called to say that he had found a pilot to take me on a flight into the Andes – himself. And to attend at 14:00 hours. I walked down the hill from Lucy’s apartment and arrived at the Vitacura airfield (alt 2,300 ft) at around 13:40, to find several gliders lined up on the runway. An Arcus M, a Ventus and a Duo Discus. The Duo was allocated to Rodrigo and me.


A 180 hp Super Cub fitted with a retractable tow rope started towing the gliders off to the 5,364 ft high local hill, the Cerro Manquehue (pronounced Man kay way) extinct volcano.

The first picture shows the early stages of the aerotow launch. Basically, Vitacura airport is hemmed in by freeway, river, houses, apartment complexes, office buildings and industrial areas. After take-off you track down the river along the side of the freeway. That's a Service Station at the bottom of the picture. A rope break would be very interesting!!!


We released at around 4,100 ft close to the western ridge of Cerro Manquehue and after scraping the ridge for a while gradually gained height in ridge lift.

We made our way north using mainly 2 to 4 kt ridge lift with the occasional thermal sometimes averaging over 9kt and occasionally using “S” turns to gain altitude before proceeding along the next part of the ridge. Passing through 10,000 ft it was time to put on our oxygen masks, but in the excitement of climbing in a 10 kt average climb rate thermal Rodrigo forgot to put his on. However, a little later he calmed down and got on oxygen without any problems. Our maximum height was about 15,000 ft. above some wispy cumulus cloud.


About 50 min into the flight we encountered quite a reasonable thermal. Rodrigo thought that we needed proof so that we could exercise bragging rights. So he took a picture of his instrument panel with his phone (see second picture). The picture shows an average climb rate of 4.9 m/s or about 1,000 ft per min.

The OLC GPS record shows a peak climb rate in this thermal of 5.5 m/s He was so excited that, there and then, he sent the picture to his mates using the preferred Chilean social media program “Whatsapp”.


About an hour into the flight we passed a blue lake in forbidding terrain (see third picture). I understand that it's the tailings dam for a copper mine. 

Maximum northerly point was 134 km north of Vitacura, and about 25km east of Chincolco airport at a mountain called Y Griega (Greek Y) a bit north of Laguna Cuadrada (the square lake). We then turned south at about 1 hour 55 min into the flight at around 13,700 ft.


On the way back we encountered a Pilatus B4 glider a little lower than us at around 12,500 ft going the opposite way. Rodrigo checked it out, but said it was from another club.

It was an easy glide back to Vitacura, averaging around 145 kph and landing there just after 17:05 after a fantastic three hour flight.

Unfortunately my Garmin logger did not capture the takeoff. My phone GPS did get the take-off on XCSoar but ran out of battery power about 2 hours into the flight.


See these .igc files:

Andes Garmin Trace

Andes XCSoar Trace


If you want to experience where we went on Google earth, the best way is to download an IGC/Google Earth viewer called IGC Replay from http://ywtw.de/igcsimen.html . This gives a 3D out the front window view of the entire flight from the .igc file in real or accelerated time. You have to have Google Earth as well.


The diagram is from the Gliding Online Contest page - www.onlinecontest.org/olc-2.0/gliding/flightinfo.html?dsId=341789


A very big “muchas gracias” (thankyou) to Rodrigo for going out of his way to get me a fantastic flight and also to Alby James for paving the way.