Experts on JATO / RATO ? how many ft does... ?

Question

a. JATO / RATO have been used in many aircrafts,

alike C-130 and fighters,,, but,

how many ft of runway run does it saves ?

- or -

b. how many percent of runway run does it saves ?

c. can choppers use them ?

d. can AV-II / JSF use them ?

e. after use, do they just drop the JATO/RATO

no matter whats down there ?

f. does Mirage III/2000 +variants have permanent

JATO/RATO under the engine ?

g. are/is there any incident/fire/crash

caused by JATO/RATO ?

Answer 1

a. It is not the amount of runway saved that is significant, but that the mission is able to be accomplished.

b. see a.

c. no

d. I doubt it. Jato is for allowing heavy transport aircraft to take off with more weight than would normally be possible, including some seaplanes, not fighters.

e. the jato units were normally installed in a door frame, and were just left there until the end of mission. When the units were burnedout, they did not weigh anything of significance.

f. I do not know why Mirage would have jato.

g. After some initial incidents, no.

You might be interested to know that Mexicana Airlines B-727 aircraft had a version of JATO permanently installed on them to be able carry more weight on the aircraft. Since maximium takeoff weight is determined by what the aircraft can safely take off with with one engine failing at committed to take off speed, the jato unit would be kicked in to replace the lost thrust. For the high altitude and high temperatures of Mexico City, the JATO gave Mexicana a real advantage. At the same time, United Airlines did not operate the B-727QC (quick change psgr to freighter) aircraft in Denver during the summer due to the heat and the higher aircraft weight of the B-727QC over a regular B-727. The difference in the aircraft was the higher weight of the QC due to the heavier floor, and the total weight of the aircraft. About 5000 pounds extra weight makes a considerable difference at 5300' altitude and summer's heat on the operating envelope of the aircraft.

Regards,

Dan

Answer 2

The original Metroliner Swearingen Sa-226 actually had a RATO bottle in the tail that was armed and available in the event of engine failure.  They were rarely used.. you had an arming key that the pilot was issued after completing the training, and you unlocked the system and armed it on the runway. The bottles were more difficult to dispose of unfired... so the Dir of Maintenance said to go ahead and light if off.. which we did on an empty leg, and the boost was impressive. The bottle remained in the tail and was removed by maintenance after the flight. It would have been a definite help in a gross weight engine failure shortly after takeoff. Since it was in the tail, there was no threat of asymetric thrust. I did see one lit off in the hangar once by some bozos clowing around with it...and it shot across the ramp and through the adjoining hangar wall... causing some concern by those people if there were any more of them lying around loose. The amount of thrust would be constant, but the impact on performance would vary with all conditions affecting any other type of take off.

Answer 3

When it was used it took about 1500 ft for take-off. The normal short field distance was 3000 ft. But this all depends on aircraft weight and air temp.

Generally it was intended for heavy loads and hot humid conditions. JATO was phased out shorty after I began flying the Hercules in the late eighties, as it was bending the airframe of our aircraft.