Hello
elephant wrote:I read with passion the report on the design of the Dieselis aircraft: certainly, we complain about the weight of the engine, but, with equal autonomy, we already recover a good part of the overweight!
I have always found that the consumption of small planes was hot.
Congratulations to the developers!
it is a beautiful construction and the performances are excelente for an airplane of this power, (I knew the report, I watch almost all that relates to the planes)
There was also the Zorch engine a 4 cylinder star 2 stroke diesel and another 8 cylinder star diesel we did the steps to mount one in cessna 180 amateur construction, the manufacturer did not want to sell .. even without warranty ..
One of the main handicap of the diesel engine on an airplane is above all the vibration, on an aluminum cell it destroys quite easily all the rivets become loose (when it rains on the wing and that we see a small trace of aluminum to each rivet it's time to see,
diesel engines are often fitted in 4130 chrome moly steel or wooden tubes. wood is excellent for vibration, but not for bad weather or large industrial construction.
For consumption the old engines that swallows for a 160hp from 35 to 40 liters per hour if you do not open it too much a 100hp is 25 liters per hour.
Normally we do not fill the tanks for small trips, we put the necessary fuel + a safety margin in case it is necessary to get around bad weather.
A plane filled to the maximum and loading to the maximum is unpleasant to pilot, you have the impression of being seated on a chair placed on a spike which oscillates. the load factor (number of G that it can absorb) rapidly decreases with weight.
The main error that we encounter with automotive engines adapt to aircraft is the poorly adapted ratio of engine speed versus propeller available on the market, in general it wants to get the maximum power from the engine it often puts reducers of 1 / 2 which makes an engine which rotates at 4400 rpm for a propeller at 2200 rpm and with a fine propeller like a knife blade, narrow, small diameter and not too large, this ultimately makes engines that heat up too much because they are used very differently than on a car.
An airplane engine is made to cruise at its maximum torque,
A propeller bites well around between 2300 and 2500 rpm, it must have a blade tip speed around 600 to 700kmh
she must pull the plane almost at the same speed as her pace, a small slip on the cruise and a greater slip on the climb
For this the diesel engine has good characteristics for aviation, an interesting power at medium speed (it gains very little at high speed) besides rarely we can get this high speed with a propeller with fixed pitch.
A plane must adapt its engine and its propeller, it is almost to make a tailor-made suit, it is necessary to make several tests on amateur aircraft manufacturers to arrive to have the good combination, powerful. (I have a long experience in this field)
The reducer and the large propellers on an airplane when we make an approach that drastically brakes the airplane no need for a shutter you land in a barely fitted out clearing, this removes the finesse of the engine stopped (this is the observation of all planes with Rotax or Subaru that I tried)
Andre
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