[Jeroen]

Originally Posted by Sutripta

If only they had connected (one of their cargo, a nuclear reactor) to some propulsive element!

It would have flown for ever, or near enouh.

It is amazing that this thing did fly around with an operational nuclear plant!

http://large.stanford.edu/courses/2018/ph241/dull1/

Jeroen

[Sutripta]

Originally Posted by Jeroen

Lockheed P2 Neptune sported two propellors and two jet engines. The jet engines were mainly used for take off. They were shut down once the Neptune was on station.

Not uncommon in the post WW2 period. But always wondered why JATO and not RATO.

Regards
Sutripta

[Jeroen]

Originally Posted by Sutripta

Not uncommon in the post WW2 period. But always wondered why JATO and not RATO.

Just to be clear: On the Neptune these jets engine are permanently fixed to the wings. They do not get dropped. Although primarily used during take off, they can also be used during other flight regime to increase vertical speed for a climb and or add a bit of speed during cruise.

Also, during submarine hunting, the Neptune might have to fly at low altitude over the sea. While on the deck, the crew would keep the jet engine at flight engine, just in case anything happened to the propellor engines. Safety margin.

The Neptunes uses two Wright Cyclone piston engines, and two Westinghouse J34 jet engines. They burn the same aviation gasoline as the piston engines.

So the jets and the propellor are completed integrated into the fuel system and the aircraft operations during different flight regimes. These sort of configurations/use-age tends to be called just auxiliary engines rather than JATO.

RATO systems tend to used only for take off and as they are rockets need their own fuel. And as rockets go, once lit, in most cases difficult to modulate power/thrust. It is all or nothing.

There are actually quite a few aircraft with auxiliary jet engines!Just stumbled across this:

https://en.wikipedia.org/wiki/Catego...ry_jet_engines


Jeroen

[Sutripta]

JATO - primary purpose is take off assist. Everything else is trying to find use for carrying that hunk of metal with you at all times. Too expensive to ditch, too thirsty to use full time. So compared to JATO, to me RATO was always a simple elegant solution.

Somehow I think when VN put forward that question, he was thinking of airframes which had been powered by either props or jets. Like the Saab, or the Vickers (I had completely forgotten about the Vickers!). Not like the Convair. Or the JATO's.

From Wikipedia

Beginning with the P2V-5F model, the Neptune became one of the first operational aircraft fitted with both piston and jet engines. The Convair B-36, several Boeing C-97 Stratofreighter, Fairchild C-123 Provider, and Avro Shackleton aircraft were also so equipped.

A few more are referred to in the Wiki Jato article.

Regards
Sutripta

[im_srini]

But on the topic of RATO, there was at least one instance where rockets were used to slow down an aircraft.

Cue : Operation 'Credible Sport', where the objective was for a C-130 to land & take-off inside a soccer stadium! The details of this operation are simply mind-blowing, especially the engineering details.

https://www.youtube.com/watch?v=fSFjhWw4DNo

I guess 'projects' like these are an aircraft engineers' wet-dream (or nightmare)!

[V.Narayan]

Originally Posted by im_srini

But on the topic of RATO, there was at least one instance where rockets were used to slow down an aircraft.

Cue : Operation 'Credible Sport', where the objective was for a C-130 to land & take-off inside a soccer stadium! The details of this operation are simply mind-blowing, especially the engineering details.

I guess 'projects' like these are an aircraft engineers' wet-dream (or nightmare)!

Thank you for sharing this. I must say you are a repository of quite a few nuggets of interesting information. Quite exhilarating this landing and take off. In the 1950s and 1960s RATO was toyed around with quite a bit till superior wing design and more powerful engines overtook that need. RATO needed a very skilled pilot and was often beyond the skill of a normal squadron jock.

On a lighter note blinded by all that smoke, the pilot...........( We can complete the sentence as we wish)

PS: please share your inputs on our aviation threads. You are rich in knowledge.

[V.Narayan]

Originally Posted by Sutripta

JATO - primary purpose is take off assist. Everything else is trying to find use for carrying that hunk of metal with you at all times. Too expensive to ditch, too thirsty to use full time. So compared to JATO, to me RATO was always a simple elegant solution.

Only problem with RATO, like with single setting afterburners is the uncontrolled full dose of energy. It leaves the pilot with almost no options in case of an unexpected situation at take off.

Somehow I think when VN put forward that question, he was thinking of airframes which had been powered by either props or jets. Like the Saab, or the Vickers (I had completely forgotten about the Vickers!). Not like the Convair. Or the JATO's.

Yes I was referring to those airframes which in one variant were all props and in another all jet. The Do-328 was a good addition to that list. I never knew it was a deliberate conversion. I always thought it was a whole new aircraft. Good learn something new.

[Jeroen]

Originally Posted by V.Narayan

Only problem with RATO, like with single setting afterburners is the uncontrolled full dose of energy. It leaves the pilot with almost no options in case of an unexpected situation at take off.

In addition, as it uses rocket fuel of some sort you will need the supporting infrastructure and staff in place to deal with that aspect of operations. Special safety protocols etc. You would need special permission to use them on most fields. As you pointed out pilots needed special skills/training.

So it might seem a simple, elegant solution, I believe in reality it is quite “special” from various angles.

Jeroen

[Sutripta]

^^^
Rato/ Jato - military aircraft only I think. Not meant for civilian use.

Regards
Sutripta

[Jeroen]

Originally Posted by Sutripta

^^^
Rato/ Jato - military aircraft only I think. Not meant for civilian use.

It did see some limited civilian use at high altitude airports. Must be quite the experience!



Jeroen

[Sutripta]

^^^
Some were designated for hot and high takeoffs. Wonder whether any actual regular civilian use.

Regards
Sutripta

PS - our AVRO pilots would have loved it!

[Jeroen]

Originally Posted by Sutripta

^^^
Some were designated for hot and high takeoffs. Wonder whether any actual regular civilian use.

The Jato 15KS was approved for civilian use somewhere in the 60s. It came in different sizes. It was used on various aircraft, including some GA aircraft such as Cessna’s.

From a very old Flying magazine, going by the introduction it is positioned for additional safety on twins (when one engines coinks out on take off), maintaining altitude whilst icing, high elevation take offs etc.

Obviously, it improves take off and initial climb performance. So even taken off from a field at sea level, where you need to clear high obstacles, could see use of Jato. (But not by me, I will pass or get a more powerful plane)

[ads11]

Originally Posted by im_srini

But on the topic of RATO, there was at least one instance where rockets were used to slow down an aircraft.

Cue : Operation 'Credible Sport', where the objective was for a C-130 to land & take-off inside a soccer stadium ! The details of this operation are simply mind-blowing, especially the engineering details.

TLDR: Operation Credible Sport was one of the options that got a fair distance during the Carter Administration. It's objective was to rescue the American hostages taken after the embassy was overrun following the Iranian Revolution.

The C-130 there is a Frankenstein of sorts what with all the many rockets protruding all over the place. I think it managed about one successful take out but burnt up on landing. The key issue was getting the timing of the various rockets to each set off at the right times. In the video you can clearly see some of them misfiring, not in sync, etc. You can imagine the ridiculous aerodynamic and physical forces these would put on the airframe, not to mention the poor pilot who had manual controls only to manage all of these. Unsurprisingly you see the wing rip off. Still goes to show what a magnificently engineered product the base Hercules was. The fact it continues to this day, in such an absolute littany of variations is testament to what good old slide rule engineering could achieve, when not held back by bean counters.

Anyway, the failure of the eventual helicopter based rescue mission by the Americans led to an incredible amount of soul searching in their military community. As a result of that nadir, the US concertedly developed their fully integrated special operations capabilities. As a result you have the tip of their spear, JSOC today.

Going back to Op Credible Sport, you can totally see that mission being executed by Ospreys today, what with their tilt rotors. In fact for those interested the USA is currently looking at a medium lift helicopter competition. One of the most interesting concepts put forward is the Raider concept by Sikorsky. It's basically a coaxial helicopter with a pusher prop at the back.

https://www.thedrive.com/the-war-zon...nce-helicopter

Coming back to the topic:
The 50s and 60s were such a wild time in aviation, I can't believe engineers got away with strapping JATO to civilian airliners! And the fact that the executives were okay with it!

[Sutripta]

Originally Posted by Jeroen

The Jato 15KS was approved for civilian use somewhere in the 60s.

Originally Posted by Sutripta

Some were designated for hot and high takeoffs. Wonder whether any actual regular civilian use.

Of course they got it approved. (Doubt whether today's regulators would have approved it!) Question is whether these were actually (civilian) used.

BTW which aircraft are approved for London City Airport?

Regards
Sutripta

[Jeroen]

Originally Posted by Sutripta

Of course they got it approved. (Doubt whether today's regulators would have approved it!) Question is whether these were actually (civilian) used.

Do not know, but probably very little, if anything the Beech in the article had them fitted.

Originally Posted by Sutripta

BTW which aircraft are approved for London City Airport?

Quite the list:

It is quite a list:

https://www.londoncityairport.com/co...roved-aircraft