So, I am going to talk about two hybrids in LTA systems.

The hybrid airship as it is said, but the correct word as Charles told me today is semi-boiant.

I really like that because it removes one of the confusions about what is hybrid.

Is it the propulsion system or is it the airship?

So I would like to reword this as semi-boiant hybrid airship.

As all of you who have interest in LTA know that there is a huge landscape of LTA systems.

In fact for the whole aircraft industry.

So we are in one small corner of that.

And the focus of our research is on lifting body dynastats which are the unconventional

airships so to say.

So Barry has already given a very detailed presentation on the applicability of cargo

airships.

Although he was focusing mostly in North Canada, but I could see the direct relevance of those

also within my own country as well as in many other areas.

In Africa for example where there is a very poor air transportation network.

So the market demand for sustainable aviation is growing.

And therefore we are looking at this multi-lobed hybrid airship.

And as I said there are two hybrids.

So one hybrid is the shape, the other hybrid is the propulsion system.

So the one that you will see in this study is a combination of conventional IC engines

coupled with electrical motors which are developing powers or getting power from the fuel cells

using the solar photovoltaics.

So this is what I was saying.

A conventional airship is considered to be a single-lobed one with a body of revolution

as the envelope.

A hybrid one would have multiple lobes.

There could be two, there could be three.

And the conventional propulsion system is to use the fossil fuel with the internal combustion

engine and then you connect it to a propeller with some kind of a reduction gearing.

Beyond that you can couple in many ways.

There could be linear hybrid, there could be parallel hybrid.

There are many combinations.

So we have studied all of them but in this particular research we talk only about a hybrid

system that is configured like this on the bottom right.

Multi-lobed airships many people know about them especially because in the recent past

there has been huge interest in airlander 10 and before that in the Lockheed Martin's

P-791 for defense applications.

So what are the merits for those who may not really be aware?

You have a best of both the worlds and also in a way worst of both the worlds.

So the good thing is that you can modulate the lift that you get.

So when you are semi-boiled you can make up for the additional lift by flying faster or

flying at a small angle to generate more lift.

So you can modulate the aerodynamic lift.

And you also come up with a very large surface area to volume ratio and that is bad from

the point of view of weight.

Now I am least qualified to talk about heavy weight.

But I still want to say that if you are heavy then you are actually eating into the payload

capacity that you could carry.

So there is a huge effort in reducing the weight of the self-weight of the airships.

Then the merits are that you can have a flat upper surface where you can have more efficient