Bike and Fly Version 3

It’s been a while since I built a flying bike or any recumbent. My friend Cody Richardson contacted me a while ago so that I build him one, so I pulled myself together and built a new iteration of the flying bike, the V3. Thank you Cody, for the energy, inspiration and confidence you gave to this project. You will get your bike. This is a Python recumbent like the V1, but with a twist.

My goals with the V3 flying bike were good rideability, extreme simplicity, low weight, and compactness in flight. The current design is a very good tradeoff to meet these goals. In the picture below the bike has an experimental pivot to find the best pivot angle for riding (will be replaced soon). The folding mechanism will be installed in the geometric middle of the bike under my butt. The front wheel has a monocycle direct drive hub. I will replace this simple hub with a geared hub when I can put my hands on one. The geared hub will come from Kervelo or MC2 Bike. I really hope that one of them will sell me a hub.

V3 prototype (testing pivot, monocycle hub and no folding mechanism).

The testing pivot was installed to find the best pivot angle. This is a Python recumbent with a negative trail and 60-65° pivot angle. A regular Python does not have direct drive hub, so this should be somewhat different in handling. I therefore wanted to find out the best pivot angle for it. I designed a pivot with an adjustable angle for testing.

The starting angle was 60°, and I was able to adjust it to +/- 6 degrees. This was perfect for testing. My tests are based on starting from 60° and going down to 56° and up to 66° Here are my findings:

  • 60°: It is pretty rideable, somewhat light and wobbly.
  • 58°: Even more light and wobbly, but rideable. Actually fun.
  • 56°: Still rideable, but too wobbly. Not fun anymore.

It didn’t make sense to have an even shallower angle, it would have been pretty much unrideable at 55° or less.

  • 62°: pretty good, less light and wobbly than at 60°
  • 63°: pretty good, but it actually felt more jerky than at 62° (It may be just an impression, 62° and 63° were very close.)
  • 64°: sooo good and smooth
  • 65°: still nice, but not so good as 64°
  • 66°: feels heavy to flop on one side or the other, barely rideable

At the end I set the pivot at 64° and it was just perfect.

Riding experience at 64°: I didn’t feel any pedal steering interference. The bike just felt right. Event at 60°, I sat down on it and went on a 100m ride from the start. I had a cornering radius of around double that of a regular MTB. This will get better in time for sure, but V3 will never have the steering agility of a good MTB. This bike is meant for going straight and in comfort for long distances.

I didn’t test its climbing performance, but I expect it to be pretty weak. Climbing was a tradeoff that I sacrificed in this design. The bike has a 45% to 65% weight distribution approximately. The driven front wheel has already 45% of the weight on it, and this gets even less on an upward slope. Will see how it works, but this bike is meant to climb in thermals not on slopes.

This was my adjustment stand. It was very basic, but it worked pretty good.

The pivot under adjustment:

I hesitated to publish these images, because they show a work-in-progress prototype, with unfinished tack welds and all the unfinished ugly details. Trust me, the bike will look smooth and awesome at the end and it will bike and fly well. 🙂

Kayaking in the Danube Delta

The Danube Delta is a vast labyrinth of canals, wetlands and lakes, which should not be explored alone and without prior experience. This is, however, exactly what I did this summer. I had just bought a Nortik Argo skin-on-frame kayak, so I took my camping gear and my phone and set off on a trip from Tulcea (port city, entry point to the Danube Delta) and wandered around pretty much aimlessly in the Delta to arrive at Sulina (port city where the Sulina canal of the Danube discharges into the Black Sea) after 3 days.

Here is my recipe. I am not suggesting that it will work for you, but it definitely worked for me. I had a little head-start as I been to the Delta some ten years ago in a canoe on an organized trip. I was therefore somewhat aware of what to expect there, but now I had to take care of my safety, navigation, food, drinking water, sleeping and logistics. Read about my plan to tackle all these aspects.


Safety-wise I didn’t have much to fear: the most fearsome animals in the Delta are wild boar (very low chances of meeting them), half domesticized/half wild bulls, jackals, mosquitos, humans with boats and maybe the cousin of the Loch Ness Monster. Of all the fauna, humans pose the only real risk to kayakers. Mosquitos are also a threat, and they have their own section down below.



Boats passing on narrow canals can make some serious waves. Most boats slow down when passing kayakers but some don’t. There are also speed boats (water busses) connecting the villages and towns of the Delta, which never slow down out of courtesy. They only use the three main canals of the Delta (St. George, Sulina and Chilia). These canals are pretty wide, but kayakers still need to paddle near the shore to avoid getting too close to the speeding boats. In my personal opinion, these boats have just too much horsepower for the complete disregard of water traffic rules and courtesy that you can see here.

To be safe of boats, you need to know how to fall in water, empty the water out of your kayak, and get back into it. I was new with my Argo, so never attempted these feats, but I was sure I could pull them off if needed. I will do an SIV (simulated incidents) with the kayak soon to genuinely feel safe when doing sea kayaking.


Weather can also be a safety issue: you need to protect yourself against the heat, sunburn and dehydration. Severe weather, thunderstorms and cold fronts can also be an issue, because of the heavy rain, hail, strong wind and cold air associated with them. You need to feel comfortable paddling in the rain (a raincoat and a kayak skirt did it for me) and also handle the cold, strong wind and waves. While paddling comfortably in the rain, I saw fishermen in their open rowing boats wrapped in blankets in a pretty miserable condition. This is their terrain, and they were much less prepared than I was, so no need to panic too much about weather. Just be prepared and take as it comes.


The Delta is huge and complex so navigation is pretty much a challenge there. However, all I used was my smartphone with a navigation app (Backcountry Navigator Demo – big thank you to them) and Open Street Map loaded onto it. I had cellphone signal pretty much everywhere in the Delta, but downloading the map for offline use was still of critical importance. Using the app and the map, I always knew where I was and where I wanted to go. For my phone to work, I used a 21-Watt solar panel. It gave me more than enough power to charge my phone and my camera.

The canals and lakes are properly mapped in Open Street Map (most of them). Clogged canals created the only surprises. Narrow (2-5 meter wide) canals can easily get clogged by drifting logs. Fishermen don’t clear them if they don’t use those canals, so logs can create pretty unexpected surprises to the kayaker. Next time in the Delta, I will take a hand saw with me (with a 25-35 cm long blade) to clear my way. I managed to push my kayak and myself over some logs, but I had to turn back and find a different route more often than that.

Searching for a way out of this lake. As I made this screenshot, I saw that there is a canal out of this lake on the upper left side of this image. Next time I will check the satellite image too for finding my way in tricky cases.

For proper navigation, flow direction is a pretty important factor to consider. You can paddle against the current on smaller canals, but it is pretty difficult to do for long stretches. On the main canals, I don’t advise paddling up-current for more than 5 km. You’ll get bitter and exhausted. In the Delta, water flows from west to east. Water flows eastwards even if the canal is oriented to the South-East or to the North-East. On canals perfectly perpendicular to the main flow direction, water is mostly still.


Having all the navigation aspects in mind, you can start your kayak trips in Tulcea and reach Crisan, Sulina or St. George (Sf. Gheorghe) downstream. Then take a speed boat or a water bus of Navrom Delta back to Tulcea. Being transported back to Tulcea, I felt like a sack of potatoes with all my pride lost, but it worked. Round-trips by kayak are possible from Murighiol to Crisan and back.

Small-scale logistics

After getting to Tulcea by car (I was too tired to catch the train early in the morning), I had to find a place where I could reach the pontoon by car, assemble my kayak in the shade and have access to the water to launch. I could find a single location which met all these criteria: right next to the Tulcea train station. Stealing is pretty common in the Dobrogea area (region between the Danube and the Black Sea), so I made sure to have all my gear under my eyes at all times.


Food was the simplest aspect to consider. I took two kilos of cherries and peaches. I love fruit, and it gives me water, sugar and a good taste. I also took a few bags of mixed dried fruit and seeds to save space, weight and eating time. To balance out all the fruit, I had a big chunk of cheese, baguettes and olives. It is pretty hot in the summer in the Delta, so I didn’t feel like eating any meat. (I do eat pork, especially in winter, when temperatures drop below -10 C.)


I took a small water filter and a two-liter plastic bottle with me. Every morning I filled the bottle with water filtered from the Danube. I drank this water for three days without any problems. On previous kayak trips, drinking water and electricity were the main limitations to where I could go. I solved these issues now with the water filter and the solar charger.



I had a small one-person tent, a foam mat and a sleeping bag. It was a lot of gear, but packing space seemed endless in my Nortik Argo. Finding a dry spot in the Delta to pitch the tent was pretty difficult though. As a general rule, when two bigger canals meet, there is some high ground between them. Sharp bends of bigger canals are also promising spots to search. After the experience of searching for high ground every afternoon, I will try to use a hammock with a mosquito net next time. Hanging it on a tree from the kayak seems like a real challenge with high risk of falling in water. If it works, though, it will remove the only limitation from roaming wherever I like in the Delta.



The entire Danube Delta from Tulcea to the oil refinery at Medgidia at the Black Sea is a huge nature reserve. You must buy a ticket at Tulcea to enter. It is around 3.5 Euro per person per week. Officers from the Danube Delta administration or the border control police may check it. There are some strictly protected scientific areas in the Delta marked in green on maps. I advise against entering these out of respect for wildlife and maybe science. Wild camping is also prohibited in the Danube Delta. On kayak trips, however, you need to camp out in the wild, because you cannot reach populated areas every day. As a true East-European, I disobey the law in this respect, but I try to have as little impact on my environment as possible.


They are the most fearsome predators in the Danube Delta by far. They come in swarms and start ferociously feeding on you at nightfall or at any time during the day in rainy weather. The only real protection against them is clothing covering all your body (including your neck and toes) and maybe staying out on open water. In bushes or any place with dense and tall vegetation, there is an abundance of mosquitos at any time of the day. When reaching a campsite with thick vegetation, just get out of your kayak, take on some clothes to cover your legs, arms and head (long trousers and a raincoat), pitch your tent quickly and get in as quickly as possible.


The Danube Delta is extremely beautiful and wild. Organized tours using power boats only show a fraction of what you can see in the Delta on a kayak trip. I wouldn’t advise a complete beginner to get into a kayak and set off on a multi-day trip in the Delta though. You need to build your skills, equipment and confidence gradually and systematically to get to a level where you can navigate the Danube Delta on your own. You need to push the boundaries constantly not to become a bag of potatoes transported from A to B. Just make sure not to bite off more than you can chew.

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.

How to read lapse rate diagram

Also known as SkewT logP diagram, lapse rate diagram is used to display air temperature and dew point temperature in function of pressure altitude.

What we can find out from this diagram:

  • thermals (if they kick off, how high they get)
  • convective cloud base and cloud top altitude
  • top and bottom altitude of any other clouds

Sources of this diagram:

Glider Forecast:

What the above diagram contains

Fixed lines (not changing in function of the daily forecast):

Grey horizontal lines: pressure altitude (in forecasting, altitude is not expressed in meters or feet above sea level, but air pressure). The altitude (m or ft) for a given pressure value varies in function of the daily air pressure, but when hovering (desktop) or tapping (mobile) on the chart, our diagram will tell you the altitude in meters.

Skewed (sloped) red lines: temperature values. The temperature axis is sloped 45 degrees to the left, so each of these thin red lines on the chart marks a given temperature value (0°C in the figure below.)

Hint: The diagram has two axis: the vertical pressure axis (=> horizontal isobars) and the temperature axis sloped 45° to the left (=> isotherms sloped 45° to the right). If all this seems too much to understand, don’t worry just read on. You’ll get what’s important below 😉

  • Green horizontal line (LOC) (if any): altitude of flying site
  • Orange horizontal line (GND): ground level

The above lines are fixed, so they don’t vary in function of the daily forecast.

Lines changing in function of daily forecast:

  • Thick red line: air temperature at different altitudes
  • Thick blue line: dew point temperature at different altitudes

These are the values forecasted for the day for different altitudes

If you hover the mouse on our diagram or tap on it in the mobile app (coming soon) you can get the air temp, dew temp and lapse rate values for a given altitude. In the above example at 1431 m ASL we have 6.4°C air temp, 5.4°C dew temp and 0.9°C/100m lapse rate. What a day!

Hint: when the red and blue lines are close together anywhere in the graph, we have condensation (clouds), because air temperature is equal to dew point temperature. So the diagram shows clouds at all altitude levels, not just convective clouds.

Thermal prediction lines:

This is the fun part: how the thermal is modelled in the diagram.

First some background information: The thermal bubble starts from the ground level. Its temperature is usually around 2°C higher than the temperature of the surrounding air (trigger temperature). The thermal bubble has a certain (constant) dewpoint temperature. As the thermal rises, the pressure around it gets lower. So the thermal bubble expands and it cools down. The cooling rate is 1°C/100m or 5 1/2°F per 1,000feet of lift (dry adiabatic lapse rate).

As the bubble rises and cools down, eventually it reaches its dewpoint temperature and it condenses to a cloud. The condensed (saturated) thermal (cloud) keeps rising further but it cools at a different rate: 0.5 ˚C/100m (moist adiabatic lapse rate).

The thermal is shown in the diagram by a tent-like structure with the dry adiabat (thermal cooling rate) in red, the constant dew temp in blue and the moist adiabat (cloud cooling rate) grey line starting from the point of condensation (top of the tent).

Now lets put everything together (merge the thermal and the surrounding air) and read the chart.

Reading the chart

  • The dry adiabat (thermal cooling rate) is to the right of the air temperature curve so the thermal bubble is warmer than the surrounding air => the thermal will kick off.
  • The dry adiabat (thermal cooling) meets the dew temp constant (blue line) before crossing the air temperature curve so the thermal will reach condensation level where the red and blue lines meet (top of tent) (here cloud base is at 1162 m at a temperature of 8.8°C).

  • The moist adiabat (cloud cooling rate) will continue to rise (the cloud rises) until it reaches the temperature of the surrounding air (red curve). The point where the grey curve intersects with the red curve is the cloud top altitude (1872m ASL).

Other cases (when the day is less perfect)

  • When the dry adiabat (thermal cooling rate) is to the left of the air temperature (red curve), the temp at the ground is lower than the average temp of the air (ground cooling effect) so thermals will not kick off (morning, evening, night hours):

  • When the dry adiabat (thermal cooling rate) crosses the air temp curve before reaching the dew point temp, we have blue thermals (thermals will stop at 916 m ASL below)

  • If the thermal kicks off and a cloud is formed and the moist adiabat (cloud cooling rate) does not cross the air temperature curve or it crosses very high, we have overdevelopment.



With the Paramotor above the Churches of Transylvania – Day 1

How it all started

It all started with a chance encounter in the parking lot. I was heading home on my home-built recumbent bicycle, Barni was working on one of his businesses or hobbies. These two overlap for him most of the time, and one of them included building a paramotor trike to take passengers with him in tandem flights. I love the company of passionate people with sufficiently crazy ideas, and he needed someone with creative welding skills. We knew each other remotely from the paragliding scene, but a partnership and friendship quickly evolved of these mutual interests.

Excitement in the garage when the trike started to take shape.

We built the trike in less than a month using his design ideas and my technical skills. It all happened in a small garage, the way other great ideas are born. The maiden voyage in a foggy October morning was an adrenaline rush. We both knew that it would work, but taking off on something we have just built with the weld seams still warm definitely gave me the strongest combination of thrilling attention and joy. The trike quickly became a taxi for many, but we had some more ideas with it for sharing another adventure.

Before the first takeoff.

We started discussing about going on a paramotor trip of several days. We would take up in the morning, fly for several hours, get down, refuel and fly some more. The theory was simple. We chose to explore a region in Transylvania once inhabited by German (Saxon) people who fled in the Communist period of Romania and in the chaos that followed immediately after the regime change. The Saxons left behind a beautiful network of tidy villages with precisely crafted houses and fortified churches.

We chose the triangle between Sighisoara (down, right), Agnita (down, left) and Medias (middle, top).

Except for a few touristy areas like Sighisoara or Biertan, most villages in this region are frozen in time. They are located in side valleys with the access road in a very bad shape, very few tourists reaching them and the Romanian and Rroma population left behind living off subsistence farming.

Fortified church in Biertan (DE: Birthälm, HU: Berethalom)

Note: All place names are given in three languages: Romanian first because we live in the present, then German, because they built these villages, and then Hungarian, because this region was under Hungarian administration for most of the time when the Saxons lived there.

The fortified churches in the village centres are beautiful combinations of a fortress and a church. Each of them is different. They are obviously the result of the effort and ideas of a closed community without a central authority directing them using force, taxes or subsidies. There are similarities, especially in neighboring villages, but each of them is very unique.

So we set off to explore this historic area. On Google Earth I created a kml file with all the sites worth visiting and the petrol stations in the area. This was all the information we used for planning our day trips each morning. As Barni had some tandems to fly on the day we were supposed to start our expedition, we arrived late in the afternoon to Agnita (DE: Agnetheln, HU: Szentágota) in the middle of our target zone. It was just right to do a one hour of flight before sunset. We visited the village of Iacobeni (DE: Jakobsdorf , HU: Jakabfalva) and Agnita.

At Iacobeni we got low in the calm evening air, and made rounds around the church tower. It was exhilarating, like flying around 800 year-old pilons in a paramotor competition. People in the village were cheering and waving at us. Visiting these untouched and innocent places with a paramotor trike and getting low above the villages felt very intense. To keep the intensity of the experience, we decided to sleep in Barni’s van instead of looking for a motel/hostel.

Having an open fire and barbecuing in the dark felt intense indeed. Even more, the sub-zero temperatures that made our beers freeze. The next morning we waited for the sun to melt and burn off the frost and off we went to visit Medias (DE: Mediasch, HU: Meggyes), some 50 km away.

I had to add this pic below, because it was imprinted in my mind when getting to sleep in the car (whenever I was not focused on keeping the cold out of my sleeping bag.)

With the Paramotor above the Churches of Transylvania – Day 2 – to Medias

Flying to Medias

Day 2 started with frost covering everything like snow. We crawled out of the van like lizards and waited for the sun to heat us up. But we rather felt like butterflies. Carnivore butterflies after the beers and the barbecue of the previous evening.

Preparations before takeoff

We had some very nice places to visit en-route, and had to land at Medias to refuel before getting back. As we took off pretty late, thermals have already started. We had to fly high above the forested ridges and inhabited valleys to avoid the rough air and occasional sinking air near the ground.

The bird’s eye view from high above gave a different understanding of the region. The most striking difference was the reduced mobility of the people who built these places, and even of those who live there today. There is very little arable land in these narrow valleys, so I can only wonder what people lived of here centuries ago. It is striking from far away that these Saxon villages had very special rules of living together.

Bethlen castle at Cris (DE: Kreisch, HU: Keresd) built in the 15th century, now mostly in ruins. It has been given back to the Bethlen family (nobles and historic governors of Transylvania) in 2007 and restoration work has been started and the castle is given a new life and purpose again after decades of Communist neglect.

Fortified church in Valchid (DE: Waldhütten, HU: Váldhíd). It is in a state of disrepair (according to the news; we could not go down to check with our own eyes because of the turbulent air) after the Saxons leaving the village, and its South tower has collapsed. Even Prince Charles intervened about the lack or bad quality restoration work done in this area.

Passing over another fortified church at Brateiu (DE: Bretai, HU: Baráthely). The village is already in the main valley of the Târnava Mare river (DE:  Große Kokel, HU: Nagy-Küküllő) with the main road connectiong Sighisoara with Medias. Brateiu is best known now for its Rroma population of artizans manufacturing copper distillers and building intricate palaces in their own style.

Arriving at Medias.

Medias is a town of regional interest, with more urban structures, especially fuel pumps that we were interested in. At the first fuel pump we could not find a proper landing place, so went on to the town centre, where there was a fairly decent grass field (in the above picture in the middle) surrounded by high and low-voltage cables, cranes, houses, and trees. Barni landed effortlessly and I was grateful for his high-level professionalism. Together with crazy ideas, it makes an excellent package.

The gas station was only 400 metres away from landing, but we still managed to gave local people a great show cruising to it. People shot videos of us riding our wheeled hovercraft on the ground to the gas station. What could be less normal than that? We parked our strange craft at the gas station and went for a light stroll and a strong coffee in the city centre disguised as normal people.

With the Paramotor above the Churches of Transylvania – Day 2 – from Medias

Flaying back from Medias

Medias city centre.

The takeoff from the patch of grass surrounded by everything you don’t want to crash into was anything but normal. There was no wind to help us. With his competition-pilot skills, Barni managed to cruise around in tight circles to avoid all obstacles and still get enough lift to climb out and above the cityscape. No filming, sorry for that, I was terrified enough not to care about the camera.

As we checked out in Medias while having a coffee, there were enough empty spaces without overhanging cables to land in the city center, so we went back to visit it again, this time in the air.

On the ride back we could fly low and get personal with a few villages with an outstanding architecture. These are still in the mainstream, with tourists visiting the fortified churches and generating income to the villages. Biertan (Birthälm, Berethalom) was the first with its castle-like church, which is the most elaborate and poetic rural fortified church in the region.

At Biertan we got down and close to the church tower again, so after visiting the village, we had to climb up again with the paramotor. We were quite heavy and the motor had a hard time pushing us, so to climb out from the valleys we needed to hitch a ride on thermals too to help us get high.

Above picture: getting some height in thermals after Biertan. Next stop: Malancrav (DE: Malmkrog, HU: Almakerék). At Malancrav they have an almost Spartan church, the complete opposite of the romanticism of Biertan (Ok, I did it, I used this word in the non-historic meaning). There is also a manor house of the Apafi family (then owned by the Bethlen family, then by the communists, then by the Evagngelical church and now by the Mihai Eminescu Trust, which renovated it properly).

Our track at Malancrav. By this time we had a pattern to our visit: arriving high, burning some altitude in spirals and wingovers, next the tour of honour around the church tower and leaving low, almost scratching the roofs.

On the way back we visited Iacobeni again. I enjoyed this low-level approach so much, that I need to share the video here too. I have a feeling that there are too many churches and towers in this post already, but hey, that was our focus here on this trip.

Landed at our base camp. That’s me, signing the picture in the lower right corner with my shadow.

With the Paramotor above the Churches of Transylvania – Day 2 – Sighisoara

Flying to Sighisoara and back

It was already late in the afternoon, but we did not stop after our trip to Medias. We refuelled, ate something and off we went to visit Sighisoara (DE: Schäßburg, HU: Segesvár), another major attraction of this region.

It was a magic flight with the setting sun flooding every building of Sighisoara with orange light, but it did not end there.

On the way back we made a small detour and flew over Noiștat (DE: Neustadt, HU: Újváros). Check how the roof on the building next to the church has collapsed.

We were after another hidden gem, however, the small village of Movile (DE: Hundertbüchlen, HU: Százhalom). They didn’t even have an asphalted road leading to the village, just some gravel full of potholes. The village is misnamed even on google maps/earth (it is called Iacobeni, which around 10 km from here).

But the church in the village has two towers spaced exactly like pilons in a paramotor competition. On the approach to the village, we came up with the brilliant idea to fly figure 8-s around the two church towers just like at a competition. Barni did not shy away from the task.

At the end we moved our camp from this lovely field to Sighisoara and stayed overnight simply in his van in a parking lot. Plain and simple.

With the Paramotor above the Churches of Transylvania – Day 3

Flying above Rupea Fortress

After spending the night in the van at the walls of the Sighisoara fortress (Burg in German) and some butter croissants at the supermarket, we headed off to do the final leg of our paramotor trip around the Rupea fortress. When we found a good field to serve as our takeoff, the early morning mist was still rising in the whitish light. It was a deafening silence as we had breakfast sitting on toolboxes, only interrupted by my phone chirping that I had new e-mail and his customers calling him to supply them with coffee.

It was time for us both to confess that neither of us could hold a regular job for too long. Getting ready for takeoff on Monday morning when everybody is in an early-hour frenzy is an experience that you cannot have if you care too much about your 9 to 5 job.

The fort at Rupea (HU: Kőhalom, DE: Reps) was the first on our trip, followed by the fortified church at Homorod (same name in all other languages).

We left the main road then and climbed across a few hills to get to Roades (HU: Rádos, DE: Raddeln). It was a completely different site cut off from the busy motorised society.

We found a fortified church with a collapsed tower. I was wondering while filming from above: how much time would it take for the German locals to rebuild this tower two hundred years ago? But it would have not collapsed back then because they maintained it properly.

We had one last stop on our journey at Viscri (HU: Fehéregyháza, DE: Weiskirich). It was a beautifully preserved robust church with thick walls and towers, a UNESCO world heritage site.

I really enjoyed that we still have so much wild beauty in this country and you can still do whatever you like to experience it. We have almost complete freedom of handling, just not hurt anybody or cause too much damage.