What Cockpit? MK V
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"Not a Caproni. A few hundred were built."
Not a Caproni or Fiat and I do not think it is a Macchi Aircraft. It is very similar to the IMAM Ro.44 but we have had that so perhaps it is the IMAM Ro.37 or 43.
Mel
Not a Caproni or Fiat and I do not think it is a Macchi Aircraft. It is very similar to the IMAM Ro.44 but we have had that so perhaps it is the IMAM Ro.37 or 43.
Mel
I have no clue about the aircraft type, but I am intrigued by what look like Thermos flasks on the bulkhead behind both sets of rudder pedals. Could this aircraft have had glider-type variometers instead of the conventional "calibrated leak" VSI?
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India Four Two
You may well be correct.
This aircraft was designed in the 1930s.
As I understand it Variometers measure the rate of change of altitude by detecting the change in air pressure (static pressure) as altitude changes. As you say in its simplest form, the instrument consists of an air bottle connected to the external atmosphere through a sensitive air flow meter. As the aircraft changes altitude, the atmospheric pressure outside the aircraft changes and air flows into or out of the air bottle to equalise the pressure inside the bottle and outside the aircraft. The rate and direction of flowing air is measured and displayed to the pilot.
I understand that newer variometer designs directly measure the static pressure of the atmosphere using a pressure sensor and detect changes in altitude directly from the change in air pressure instead of by measuring air flow. These designs tend to be smaller as they do not need the air bottle.
The term "vertical speed indicator" or "VSI" is most often used for the instrument when it is installed in a powered aircraft as against the term variometer when used in a glider.
Mel
This aircraft was designed in the 1930s.
As I understand it Variometers measure the rate of change of altitude by detecting the change in air pressure (static pressure) as altitude changes. As you say in its simplest form, the instrument consists of an air bottle connected to the external atmosphere through a sensitive air flow meter. As the aircraft changes altitude, the atmospheric pressure outside the aircraft changes and air flows into or out of the air bottle to equalise the pressure inside the bottle and outside the aircraft. The rate and direction of flowing air is measured and displayed to the pilot.
I understand that newer variometer designs directly measure the static pressure of the atmosphere using a pressure sensor and detect changes in altitude directly from the change in air pressure instead of by measuring air flow. These designs tend to be smaller as they do not need the air bottle.
The term "vertical speed indicator" or "VSI" is most often used for the instrument when it is installed in a powered aircraft as against the term variometer when used in a glider.
Mel
Mel,
You give a good description of a glider vario, but until I saw your picture of the "unknown Italian job", I didn't think they were used in powered aircraft, because they are far too sensitive.
Mechanical glider varios have a light, spring-loaded vane, that is deflected by the air flow to or from the reservoir, giving a time constant (delay) of about 3 seconds.
All powered aircraft VSIs that I was previously aware of use the case of the instrument as the air reservoir and an ASI-type bellows to measure a pressure differential caused by a calibrated orifice. The time constant is much longer than 3 seconds, but I don't know how much.
A picture is worth a thousand words, so here's one: http://www.aeromech.usyd.edu.au/aero...ments/VSI.html
It's not quite the same as I remember from my UAS ground school days, but maybe my memory is fading.
So I am still interested to know if glider varios were commonly used in powered aircraft in the past - apart from glider towplanes.
You give a good description of a glider vario, but until I saw your picture of the "unknown Italian job", I didn't think they were used in powered aircraft, because they are far too sensitive.
Mechanical glider varios have a light, spring-loaded vane, that is deflected by the air flow to or from the reservoir, giving a time constant (delay) of about 3 seconds.
All powered aircraft VSIs that I was previously aware of use the case of the instrument as the air reservoir and an ASI-type bellows to measure a pressure differential caused by a calibrated orifice. The time constant is much longer than 3 seconds, but I don't know how much.
A picture is worth a thousand words, so here's one: http://www.aeromech.usyd.edu.au/aero...ments/VSI.html
It's not quite the same as I remember from my UAS ground school days, but maybe my memory is fading.
So I am still interested to know if glider varios were commonly used in powered aircraft in the past - apart from glider towplanes.
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No takers?
Quite surprised that it has lasted this long. Evansb with his suggestions of Caproni Ca 133 and Savoia-Marchetti S.73 was correct in respect of nationality and era, also regarding the number of power-plants.
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evansb
Sorry about the delay, it is the Maachi C100.
I am not sure if the cockpit windows were also behind the pilot's heads, if so it must have been quite an experience to see those three props spinning over one's shoulder.
You have control.
I am not sure if the cockpit windows were also behind the pilot's heads, if so it must have been quite an experience to see those three props spinning over one's shoulder.You have control.
