FAQ
Who is flying the survey?
The survey will be managed and flown by Bell Geospace.
Bell Geospace owns and operates three aircraft which have been specially modified for geological mapping. The company has over twenty-five years of experience in geophysical surveys and a wide variety of experience across many countries and conditions. There will be one aircraft operating on the survey in Niedersachsen.
What is the location of the survey?
Please refer to the map on our home page which shows the flight area planned for late October/early November.
Red: 5,000km² survey area
Blue: 8km turning circle area
White: Indicative flight lines
how high will the plane fly?
The plane will fly at a height of 80 - 300m, depending on the location. The North-South flight lines will generally be spaced at 2,000 metre intervals, and the East-West flight lines spaced at 8,000 metre intervals. The aircraft may also fly an infill survey to 500 metre intervals over a 20 x 20km area.
Each flight line generally is only flown once. On infrequent occasions flight lines are repeated but it is rare to ever be flown more than two times.
What is being measured?
The Air-FTG® sensors are measuring gravity to measure changes in density. The magnetometer is measuring the Earths magnetic field.
We are looking for the minute changes in Earth's density distribution in all directions (tensors) – the measurement is known as Eötvös.
The instrument used to collect the gravity information is known as a gradiometer, which is the size of an average washing machine. It holds technology called accelerometers. Accelerometers can also be found in your mobile phone. The accelerometers are on plates placed at opposing angles and then placed inside an umbrella shape to get the measurements that we need.
What type of aircraft is being used?
The Basler BT-67 is an ideal plane for this survey.
Bell Geospace required a plane with two engines for added safety, low sensitivity to turbulence for improved data quality, a strong track record of reliability, and good endurance for increased international reach. The Basler BT-67 met these requirements. The BT-67 is a converted DC-3 aircraft fitted with twin turboprop engines and state-of-the-art digital avionics. It combines excellent productivity with logistical efficiency.
Why is a survey taking place?
The purpose of the survey is to collect geophysical information on the properties of the rocks below the ground.
By carrying special technology onboard, the Bell Geospace aircraft is able to sense and measure geological properties which cannot otherwise be seen. Essentially, we are able ‘see’ through to the Earth’s subsurface.
The survey in Niedersachsen is collecting information to make geological maps. These maps will be used for evaluating the geothermal energy potential in the area.
The information collected will be used as a part of a wider consideration on future steps for geothermal exploration activities in the area. Data acquisition does not represent any excavation activity. Bell Geospace is not a mining company.
HOW loud will it be? if I have livestock, will it bother them?
The plane is designed to be as quiet as possible, and does not fly quickly.
It is quieter than a helicopter flying at the same altitude. If someone is standing directly underneath it, the volume is similar to that of a blender running in your kitchen, or a passing vehicle going at 50 km/h.
Please see the video to the left (which shows the plane flying at 100m over a horse and rider) to understand how this will look and sound.
When will flights take place?
Flights will take place daily each morning starting from around 8am. We expect to be flying for up to five hours per day.
Flights may continue on weekends. We expect to be flying for 15 days from the middle of November.
Inclement weather (excessive wind, storms, clouds) can cause flight delays, as can unforeseen circumstances such as unannounced military practice or unexpected wild animal/bird activity.
Should I have any concerns?
The survey is safe and is an entirely passive process.
Neither the technology on the aircraft, nor the aircraft send out any signals or booms into the Earth.
Geophysical data is collected by measuring gravity and derivatives of gravity (which is known as gradiometry) with the Air-FTG® sensors. No pictures or video are being taken.
Livestock/horse owners can follow the plane on our live tracker page, should they wish to take precautions at the time of the flight.
