Tips and Tricks for Flying in the Flatlands

In the previous article I explored possible cross-country routes, possible distances flown and managing controlled airspace in the southern Romanian flatlands. In this article I summarize my experience of flying in the flats: how to do safe and efficient takeoffs on a payout winch, how to thermal in the flats, and how to fly cross-country.

Winch Types

There are two main types of winches in paragliding: pay-in and pay-out winches. Pay-in winches are stationary devices. A helper pulls out something like 1000-2000 metres of line, the pilot hooks up to this line, and the winch pays in (pulls) the line while towing the pilot up in the air. Payout winches work the other way. They are mounted in a car (or boat, quad or some other vehicle). A short (around 50 m) line is payed out. The pilot hooks up to the end of the line, lifts and stabilizes the wing above his/her head, and the car starts moving while paying out the line with a certain brake pressure applied to it.  We used payout winches in the flatlands, so I will explore this option further below.

Payout Winch Takeoff

What do you need? On the winch-side of the line you need:

  1. A ~2 km long straight road with no or very little traffic, and no trees, power lines or buildings for the line to fall on them
  2. A car with sufficient off-road capabilities to drive on this road at a speed of up to 45-50 kmh (worse roads require more rugged cars).
  3. A payout winch, which is sufficiently automated to be operated by the car driver
  4. A driver/winch operator; he can also drive you to the takeoff, tow you and then retrieve the car/pilots.

The pilot needs:

  1. The most important requirement for the pilot are proper ground-handling skills. You need to be able to handle the wing in zero wind, cross-wind, strong wind, whatever the conditions are; stabilize it above your head; give the start signal to the driver; and take off pulled by the line synchronized with the car/winch operator. All these scenarios require good ground-handling skills.
  2. A tow release is the only equipment you need in addition to hill launch.
  3. Good communication with the driver. We use headsets and a mobile call with the driver for takeoff. Radio communication is also required for release because the phone call usually cuts out above 500m AGL.

Risks at Towing

The major risk is messing up the launch process, because at launch you are close to the ground, and any incident can quickly escalate into something very bad. I had a close call when once in a hurry I hooked up the tow release somehow asymmetrically (or the tow release got caught in my cockpit, not really sure). At launch, the release pulled the right riser far more than the left one, and I started flying at 45 degrees to the tow line to the left and gaining very little height instead of following the car and going up. I had precisely 2-3 seconds from launch to pull the release before being pulled out from below the glider and hit the ground hard. I pulled the release just in time, but I came very close to a serious accident. The best way to avoid any major surprises at takeoff is to apply brake pressure on the tow line slowly and gradually (the brake pressure starts pulling the glider up in the air).

After takeoff, the only major concern of the pilot is keeping the glider perpendicular to the tow line (if the wing is facing a different direction than the tow line, the pilot can be pulled out from under the wing and nasty things can happen again). Use mostly weight shifting and little brake inputs; use the brakes as little as possible (not to stall the glider).

Flying technique

Disclaimer: I am far from being an expert in cross-country flying, but I like to reason and write about flying. In this article I present my personal strategy and ideas that I use to fly in the flatlands. The section on flying fast and efficiently should be written by someone else though. I fly rather slow.

In my experience, if the day is good, it is best to take off starting from 11 am to 12:30 pm. This is the first booming period of the day, when the first decent cumulus clouds form and you can expect to climb well. If the day is slow, and the lapse rate is rather bad, the first good climbs are usually possible at around 3 pm.

After Releasing the Line

In the first climb, I try to recognize the pattern of the day: the wind direction and strength at different altitudes (how much I drifted while thermalling). Every few minutes I check my ground speed for an entire 360 turn. I also pay attention to possible altitude levels with weak lift or disorganized thermals (wind shear or inversion); in which direction I had to extend my circles at a given altitude level to center/find the core; how clouds evolved around me and above me while I was climbing (cloud cycles). After the first thermal, I usually have a first strategy whether I should follow clouds or the ground (sunlit regions, thermal sources and triggers); which clouds to go to; if it is worth to go to nice fat clouds or rather aim for the small fluffy stuff. This pattern generally holds up for the first hour or two of flight.

Flying Cross-Country

As the day passes and as I cover some distance, the conditions may change, but the inversion levels, thermalling strategy and cloud cycles/patterns remain the same for some time. The next challenge is observing how the day and conditions change and adapting my strategy to these changes. Generally things are pretty fast and easy from 11 am to 1:30 pm.

Then there is often a period of 30 minutes to one hour of weak lift, and fuzzy clouds. In this period your only option is to slow down, be patient and try to stay up. You simply core every weak lift you can find, don’t go on long glides with speed, and don’t give up fighting to stay up until you have actually landed.

If there was a thermal lunch break and you survived this period, you are generally rewarded with a few hours of booming conditions, strong thermals and reliable lift. How long this lasts depends on the number of daylight hours (22nd of June being the longest day) and the quality of the air. Now you can fly fast, only take the strong stuff and use as much speed as possible.

If there was no overdevelopment in the booming period, the last part of the day brings weak but steady lift, and nice orange colours in the sky. You need to slow down again, and you can cover an additional 10-30 kms just by patiently circling in the weak lift and drifting with the wind until the day ends completely. This part of the day feels the most rewarding and relaxing: just do your circles in the 0-1 m/s lift and drift with the wind.

Using the Wind

Flatland flying requires a pretty different strategy than flying in the mountains. With no ridges, peaks and valleys to define thermals, wind has a much more important effect on how you should fly. You need around 20 kmh wind to fly efficiently in the flats. With 20 kmh wind, you cover distance with a constant speed of 20 kmh even if you don’t go on a glide. The maximum wind speed for safe flying is somewhere around 35 kmh at ground level. With stronger wind, the wind determines where you go; you have fewer options to choose a landing place when getting low, so you can be blown into villages, cables or trees. Flying cross-wind to avoid areas of controlled airspace, towns/villages or lakes gets more difficult.

Due to the strong wind, thermals tend to be organized in bands along the wind direction, so after climbing high, the best option is usually gliding directly downward to find the next lift.

In case of weak to no wind, you may need to fly in a zigzag pattern to cover the best thermal sources or to follow the clouds scattered all over the area. Flying triangles in the flats is more difficult than in the mountains, because there are no mountains (especially ridges) to organize thermals in bands.

Finding Thermals

When looking for thermals, you can follow the clouds or the ground or a combination of these two. Clouds have a different lifecycle every day and this can even change every few hours, so it is best to find the pattern that applies to your day and period of the day. There are days when you will find a good thermal under every cloud you go to. On other days big fat clouds never have a good thermal under them and you should rather go to the young and weak clouds or even out in the blue. It all depends on the day and the patterns you found.

With every climb, try to understand the patterns that worked at that time, and try to apply them for your next move. Obviously, you also need to recognize any changes in the day; adapt to it, and refine your strategy instead of blindly applying what worked in the previous hour or day.

When following the ground, look for sunshine, thermal sources, triggers and the wind. Plan your route to cover as many good possible sources of thermal as possible. It is all statistics: if you fly over many good thermal sources, you will eventually bump into one. The key is looking for contrast. If everything is covered with snow, you may find a thermal above a wetland with liquid water. So look for the hottest, driest, darkest and bushiest fields. These are my main criteria for selecting good thermal sources, in this order: the field must be in the sun and be the driest of all, it should be dark in colour and should have vegetation (grass, wheat, rape seed, bushes). Villages are usually good thermal sources too. If there is wind, the thermal is triggered at the downwind end of this field, where there is a good trigger. With weak to no wind, thermals may get triggered right in the middle of the field.

Triggers can be anything, which give the strongest contrast in the area. A trigger can be the border between a dry and a wet field, a tree line, a tractor, a road, a river, a ridge. The terrain feature giving the strongest contrast is usually the best trigger if it is close enough to a thermal source.

In one flight I followed a 50 m high ridge in the flats for 40 km from Giurgiu towards Calarasi. It was set exactly in the direction of the wind and it gave a reliable thermal just like a ridge in the Alps. There I learned the idea of looking for contrast. If everything is flat, even a 50 m high ridge can give reliable thermals.

Please share your stories and ideas about flying in the flatlands in the comments below! Your ideas will help others and telling them will even help you reasoning about them and becoming a better pilot.

Flatland Flying in Romania

After moving to Bucharest, I have dreamed for long about flying in the Romanian flatland. The flats stretch for over 350 km West to East and for over 100 km in North-South direction. Even with the restricted airspaces: Bucharest TMA and Craiova CTR there is enough free space left to fly our paragliders as much as we can and even break national records.

The maps in this article were generated using XC Planner.

Hill Takeoffs

The major issue is taking off: the only natural takeoffs usable for flatland flying are located at Breaza and Mizil.

Breaza is a very good flying site for SW to W wind directions of up to 25 kmh and for thermal conditions. Breaza has great XC potential, with possible flights to Braila/Galati (to the East) or Focsani/Vaslui (to the North-East). The only issue is the military base located at Bobocu with a NOTAM set for most weekdays blocking most realistic cross-country flying routes. So Breaza is an option only for the weekends. For ridge soaring, it usually has some very nice magic air in the evenings with the sun setting behind the plains similar to soaring at the sea coast.

The takeoff hill at Mizil is rather small (less than 100m difference between the hill top and the base), where conditions can get pretty crazy with strong lift and sink and lots of trees, houses and cables at the bottom of the hill to worry about. When flying to the North-East the pilot must fly over hills with lots of forests, and somewhat difficult terrain with few options for retrieval.

Winch Towing

The third and most flexible option is winch towing. Owning and operating a winch is a pretty costly and time-consuming affair, so I was more than happy to hear that in the last couple of years there were two guys/groups who purchased and started operating payout winches. For those who don’t know, a payout winch is mounted in/on a car. At takeoff only 50-100m cable is paid out. The pilot hooks up to the cable. The car is moving during takeoff at a speed of 20-50kmh, pulling the pilot at the end of the cable. The winch pays out the cable with a certain brake pressure applied. The pilot is lifted to approx 500-700 m above takeoff altitude. For towing you need a reasonably flat and reasonably straight road of around 2 km in length without cables, forests, tall trees, where an offroad car can go with a speed of up to 50kmh.

Winch Takeoffs and Flying Regions

The winch has the advantage that it can move to any area from where paraglider pilots can fly long cross-country flights along the prevailing wind, thermal conditions of the flight region and restricted airspaces. We usually have very good flying conditions after a cold front coming from the West or in the cold and dry air moving in from the East or North-East.

Flying along the Danube

The easiest flying route in the Romanian flats is located in the West to East direction along the Danube. We usually take off near the towns Caracal or Alexandria and fly towards Calarasi. The only challenge here is a rather narrow section bordered by the Bucharest TMA and the Danube (14km at its narrowest) especially in case of strong wind. The longest theoretical cross-country distance possible here is 265km. Flights of up to 200km are pretty realistic if the conditions are right.

Flying East to West on this route (i.e. backwards) is also possible from a takeoff near Calarasi (have not tried it yet as of writing this article in July, 2018).

Flying along the Sub-Carpathian Hills

The Bucharest TMA stretches well into the Carpathians in the North. The TMA starts at 4500Ft AGL (up to FL175) in this area. Cross-country flights are possible by not going over a maximum altitude of 4500ft/1350m AGL, but they are still pretty difficult. We therefore leave the TMA to the West towards Pitesti and take off right at the border of the TMA and fly to the West or South-West. Possible cross-country distance is 200km to the West or 130 km to the South-West.

Flying East to West along the Sub-Carpathian Hills

Flying to the West (above) and to the South-West (below).

Flying Triangles in the Flatland

Flying triangles in the flats is rather difficult. In the flats there are no mountain ridges to organize thermal activity. If there is no wind to organize them in rows of lift and sink, pilots may need to fly in a zig-zag pattern to connect thermal sources/triggers or cumulus clouds which makes cross-country flying very inefficient. With that said, flying triangles in the flats is still possible and much fun. In the Romanian flats, we have a big area bordered by the Buchatest TMA (in the East), Craiova TMA (in the West), the Danube (in the South) and the Sub-Carpathians (in the North). 300km long triangles are theoretically possible here, but pilots can reasonably expect to fly 100 to 150km triangles.

A reasonable route (already flown in 2017) starts at Alexandria, continues to Rosiorii de Vede/Dobrotesti, then to Turnu Magurele and back to Alexandria.

Flying in the East

We have not explored flying in the Eastern part of the flats, but it is also possible, from Galati to the South/SSW. This area is delimited by the Danune (flowing from the South to the North) and the Buzau/Bobocu NOTAMS and the Buchatest TMA.

Flying in the flats is not less technical or easier to do than in the mountains, but it is probably safer. There are lots of unexplored opportunities in the Romanian flatlands, so make friends with pilots and groups operating winches and fly.