Sideways quick stops

[RW-1]

I would go for a combanation of altering heading and gaining alt as rapidly as possible. Of course in the "typical" pre-mishap sequence, it would really come down to your position when you saw the obstruction, closure rate at that time, etc. Would you have the time to avoid it within the heli's (and pilot's) capabilities.

Of course, as with anything, the issue is not to get into the situation in the first palce if one can avoid it

[bosher]

Forgive me if this has allready been mentioned but,

Although it has not happened to me (in 4000 hours in R22s) it is not unheard of of the old engine to cut in the flare(during a quickstop). Expecially if you have not been religious with the carb heat!!!

Going sideways at this point just seems bloody stupid!!!

If a "sideways quickstop" stops you a little quicker, and you need this technique to avoid hitting something, then why were you there in the first place.

I think there is more "showing off" involved here then operational necessity.

[yxcapt]

Thanks guys! Here's what I've learned:

A sidways quick stop may get you stopped faster than a forward quick stop but not without increasing the risk/exposure to mast bumping, vortex ring state, and unknown side loads to the tail structure.

Increased airspeed agravates the situation.

Avoid the situations that would nessate the need to use a sideways quick stop.

The benifits do not out weigh the risk.

[Airspeedintervention]

The sideways quick stop was always one of my favorites in the OH-6. Cobra's couldn't quite duplicate it and always seemed to be thrown off by the sudden effectiveness of it.

[DennisK]

Just out of interest, I've used the sideways q-stop from around 50-60 knots as an opening manoeuvre for my standard display for some 35 years. (1245 public displays) Even the large airframe area Enstrom 480 and 280 series handles the manoeuvre without difficulty. Perhaps the sideways disc angle achieved is the factor since, at say 45 degrees, it would seem the reversed relative airflow is similar to an autorotation entry. Dennis K

[HowlingMad Murdock]

Quick stop display-DennisK

Nice....have seen videos of some of your displays on - youtube - fantastic flyin' - be great if you could post when you are displayin' next.

[ascj]

Interesting thread. it looks as though the sideways quickstop has become a magical manouver ready to destroy any 22 thats not involved in mustering!
surely it is just part of a downwind quickstop.

[DennisK]

Display

Next public display. Hop Farm, Beltring, Nr. Tonbridge, Kent. 17th/18th Sept. 300C. Then at Helitech, Duxford, Enstrom 480, 27th/28th Sept. AH64 Apache also displaying at Duxford. Dennis K

[ianp]

Wow, cool thread.

My two penneth' worth: A "sideways" quickstop, as described at the start of the thread, only works really well in a tandem (CH47/Chinook). This kind of supports comments by Nick that the majority of deceleration is produced by the main rotor/rotors.

In any conventional helicopter I would join other commentators on this thread in that a rapid application of a big sideslip is not a nice place to be. Mainly due to potential overstress and also in the event of power loss at low level.

Also don't forget you may experience different low speed handling and engine/rotor governing characteristics depending on which direction you are turning.

[rotorrookie]

Not recommended maneuver if your bird is a AW-139

[Flyting]

If a "sideways quickstop" stops you a little quicker, and you need this technique to avoid hitting something, then why were you there in the first place

Exactly... why are you trying to teach a PPL, or a CPL for that matter, this menouvre when they shouldn't be in this situation in the first place...??? This is a technical operational menouvre utilised to get your tail rotor away from anything that might rip it off, whether it is being thrown around for some reason close to the ground i.e. mustering or game capture, or as a quickstop menouvre when wanting to remain at a very, VERY low level, under radar/visibility of enemy i.e. in a military capacity.






If it is done correctly, technically like a normal quick stop, there isn't really any difference...

• you shouldn't get mast bumping if the disk is kept fully loaded,
• LTE is unlikely as the t/r disk is tilted at an angle (like the main rotor is tilted so you won't get vortrex - without sinking), and the speed isn't that fast when the t/r is kicked sideways
• the tailboom shouldn't come off as you're not throwing the tail out at 100kts - it should only be swung out towards the end of the menouvre if you're at a high speed, otherwise you're going way too fast way too low...!

besides the fact that if it does go wrong at the end (engine failure or t/r strike, you're going rolling instead of sliding.

I was involved in game capture and instruction for a few years and I was taught this menouvre by an ex-RAF test pilot, NOT TO BE TAUGHT TO PPLs... and only as an OPERATION menouvre for situations where it might be neccesary......!

surely it is just part of a downwind quickstop

not at all.... a downwind quickstop is a where the heliopter is turned through 180 deg in a quickstop menouvre so that the nose is pointing into the wind at the end...




2 ways of doing it.....

1. start the quickstop and then turn ending with a min of 30kts at 30 deg into wind and then coming to a stop
2. turning first and then executing a normal quickstop as you are coming out of the turn...

and again, this isn't a normal PPL menouvre, even though it is taught in some parts of the world. You shouldn't be in the situation of being low level downwind, unless for operational purposes in a commercial operation where you have no other choice.
The downwind quickstop is also a military menouvre to bring the helicopter to a landing spot (into wind) while maintaining very low level under enemy eyes...


The unfortunate thing about a lot of military menouvres is they look fantastic when done, and they tend to creep their way into the general public, where newbies have seen such menouvres and want to know how to perform them... Instructor, be careful what you teach your students as they are, 9 out of 10 times, going to do them showing off to their mates.... and always happens....and the CAA always asks "who taught him that?" Keep the specialist teaching for commercial pilots only where it may be neccesary and keep the normal for others who don't need it...