DE202021002372U1 - Thermal indicators for gliders - Google Patents

Abstract

Device for thermal display in gliders, which is integrated in evaluation electronics (5) and consists of a housing (6), a display (7), an electronic buzzer (8) and a microcontroller (9) and is connected to an electrical power supply ( 10) is connected, characterized in that the evaluation electronics are connected to at least one sensor element (1) installed in the ventilation inlet (2) of the aircraft cockpit (3) for measuring relative humidity, air pressure and air temperature.

Description

Technical area

The device is a display device that is preferably used in a glider with the aim of automatically informing the pilot by means of an optical and acoustic signal when he is flying through an updraft area (“thermal”).

According to the requirements of the Utility Model Act, only devices are to be protected as utility models, but not processes. If reference is made in the description to methods, these references serve only to illustrate the device for which protection is sought with the appended claims.

State of the art and physical background

Thermal, i.e. the rise of air masses triggered by solar radiation, is the most relevant meteorological effect in gliding. Variometers are commonly used to find thermals. They are standard equipment on gliders. Variometers are based on the measurement of static air pressure and the detection of changes in air pressure when climbing or descending.

However, variometers have two major disadvantages. On the one hand, they do not show the thermal directly, but only the rise of the aircraft caused by the thermal. The thermal must first accelerate the aircraft upwards before the variometer reacts. The display is therefore delayed by several seconds. On the other hand, variometers also react to horizontal gusts of wind and then detect an apparent updraft that actually does not exist. Variometers are not ideal for the immediate and delay-free display of thermals, also known as "beards".

In DE 1 291 546 A and DE 2 248 466 A methods are described in which thermal sensors are used to detect updrafts. It is assumed that rising thermal air is warmer than the ambient air. However, this is not the case at the altitude normally flown through by gliders. For this reason, those procedures could not prevail in practice.

Thermal arises because the rising air has a lower density than the surrounding air. The main reason for the lower density is the higher humidity within the thermal. The relative humidity of the rising thermal air increases continuously, as the air temperature decreases with increasing altitude and colder air can absorb less moisture. At the cloud base, the relative humidity reaches 100% and the water vapor condenses. The ambient air outside the thermal also usually becomes more humid with increasing altitude to below the cloud base, although not with the same gradient as the thermal air.

Rising thermal air maintains a largely constant mixing ratio. The mass of water contained in the water vapor per mass of dry air hardly changes during the ascent. This means that the mixing ratio of the air can be used as a reference variable that is independent of altitude. An altitude-independent reference value is required because the flight altitude of a glider changes continuously. From a measured change in the relative air humidity, it would not be possible to tell whether this change is due to flying into more humid thermal air or from a change in flight altitude. The mixing ratio of the air can be calculated from the relative humidity, the air temperature and the air pressure.

The use of moisture sensors to localize thermal updrafts from the is previously known U.S. Patent 6,012,675 . In it, two moisture sensors attached to the two ends of the wing are used to detect the entry into the thermal. The aim of the two sensors is to use different moisture values on the right and left wing to detect which side of the aircraft the beard that is being flown into is located. It is assumed that one of the two ends of the wing is closer to the center of the beard than the other, so the humidity is higher there. The pilot is then shown in which direction he should circle in order to find the center of the beard. However, the method described there has the disadvantage that it analyzes the moisture only at the respective flight altitude. There is no altitude-independent reference point and a change in altitude of the aircraft can lead to a misinterpretation with regard to entering thermals.

Object and advantages of the invention

The invention specified in claim 1 is a device for the immediate display of thermals. For this purpose, the device software emits an acoustic signal and a visual indication in a display when it detects the "thermal" status after evaluating the physical properties of the ambient air. The disadvantages of the previously known techniques do not arise.

The device immediately indicates to a glider pilot that he is entering a thermal. This makes it easier for him to circling in the beard and more quickly faster centering than with conventional variometers, which enables a faster gain in height.

1 shows a possible installation situation of the device in the cockpit of a glider while 2 describes the basic structure.

A sensor element (1) , which measures air temperature, air pressure and relative humidity, is located at the ventilation inlet (2) of the cockpit (3) of a glider (11) Mounted so that it is continuously blown by the air flow from the ventilation. If there is no suitable ventilation inlet, the sensor element can also be on the outside of the glider (11) to be assembled. Via a cable (4) the measured values are sent to the evaluation electronics (5) transfer. The data transfer between the sensor unit (1) and evaluation electronics (5) preferably takes place via a serial data bus.

The evaluation electronics (5) consists of a housing (6) , a display (7) , an electronic buzzer (8th) and a microcontroller (9) . She is like that in the cockpit (3) that the pilot installed the display (7) see and the buzzer (8th) can hear.

The device is connected to an electrical power supply (10) connected.

• • Die Messdaten zu Lufttemperatur, Luftdruck und relativer Luftfeuchtigkeit werden vom Sensorelement (1) erfasst und von der Software des Microcontrollers (9) in der Auswerteelektrönik (5) eingelesen.
• • Aus den so erfassten Messdaten berechnet die Software das Mischungsverhältnis der vom Segelflugzeug durchflogenen Luft.
• • Beim Einfliegen in die Thermik erhöht sich das Mischungsverhältnis der durchflogenen Luft, was die Auswerteelektronik (5) erkennt und daraufhin den Status „Thermik“ setzt.
• • Die Software veranlasst die Anzeige des Status „Thermik“ im Display (7) und das Einschalten eines elektrischen Summers (8).
• • Aus den physikalischen Daten der Luft innerhalb und außerhalb von Thermik können die jeweils unterschiedlichen Luftdichten berechnet werden. Aus den Dichteunterschieden wird eine theoretisch mögliche Aufstiegsgeschwindigkeit der Thermikluft ermittelt und ebenfalls im Display angezeigt.
• • Beim Verlassen des Bartes sinkt das Mischungsverhältnis der durchflogenen Luft vom höheren Thermik-Wert auf den niedrigeren Wert außerhalb von Thermik. Die Software schaltet auf den Status „Vorflug“ um.
• • Die Software veranlasst die Anzeige des Status „Vorflug“ im Display (7) und das Ausschalten des Summers (8).
• • Der Status „Vorflug“ bleibt so lange erhalten, bis ein neuer Bart erkannt wird.

On the microcontroller (9) a software is running that carries out the following functions at least every second:

• • The measurement data for air temperature, air pressure and relative humidity are taken from the sensor element (1) and recorded by the software of the microcontroller (9) in evaluation electronics (5) read in.
• • From the measurement data recorded in this way, the software calculates the mixing ratio of the air flown through by the glider.
• • When flying into the thermal, the mixing ratio of the air flown through increases, which the evaluation electronics (5) recognizes and then sets the status "thermal".
• • The software causes the status "Thermal" to be shown in the display (7) and turning on an electrical buzzer (8th) .
• • The different air densities can be calculated from the physical data of the air inside and outside of thermal. A theoretically possible rate of ascent of the thermal air is determined from the differences in density and is also shown on the display.
• • When leaving the beard, the mixing ratio of the air flown through drops from the higher thermal value to the lower value outside of thermal. The software switches to the "pre-flight" status.
• • The software causes the status "Pre-flight" to be shown in the display (7) and turning off the buzzer (8th) .
• • The status "pre-flight" remains until a new beard is recognized.

List of reference symbols

(1)

Sensor element

(2)

Ventilation inlet

(3)

Aircraft cockpit

(4)

cable

(5)

Evaluation electronics

(6)

casing

(7)

Display

(8th)

electronic buzzer

(9)

Microcontroller

(10)

Power supply

(11)

Glider

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 1291546 A [0005]
• DE 2248466 A [0005]
• US 6012675 [0008]

Claims (9)

Device for thermal display in gliders, which is integrated in evaluation electronics (5) and consists of a housing (6), a display (7), an electronic buzzer (8) and a microcontroller (9) and is connected to an electrical power supply ( 10) is connected, characterized in that the evaluation electronics are connected to at least one sensor element (1) installed in the ventilation inlet (2) of the aircraft cockpit (3) for measuring relative humidity, air pressure and air temperature. Thermal indicator after Claim 1 , characterized in that the microcontroller (9) switches on the buzzer (8) and shows the status "thermal" on the display (7) when the humidity value recorded and evaluated by the sensor element (1) indicates that thermal air has flown through. Thermal indicator after Claim 1 , characterized in that the device software uses the values measured by the sensor element (1) to calculate a theoretically possible updraft strength in meters per second (m / s) or feet per minute (ft / min) and shows it to the pilot in the display (7). Thermal indicator after Claim 1 , characterized in that the device software uses the values measured by the sensor element (1) to calculate a theoretically possible updraft strength in meters per second (m / s) or feet per minute (ft / min) and, depending on the updraft strength, a model in frequency or pulse width emits an acoustic signal via the buzzer (8). Thermal indicator after Claim 1 , characterized in that the sensor element (1) does not measure the relative humidity, but instead the absolute humidity, the mixing ratio or the water vapor pressure. Thermal indicator according to one of the preceding claims, characterized in that the sensor element (1) is attached directly to the housing (6). Thermal indicator according to one of the preceding claims, characterized in that the sensor element (1) is attached to the outside of the aircraft. Thermal indicator according to one of the preceding claims, characterized in that the sensor element (1) is wirelessly connected to the evaluation electronics (5) via a radio link. Thermal indicator according to one of the preceding claims, characterized in that the device is integrated in an electronic variometer, in a navigation device or in a data logger.

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