Downwind approaches
Joined: Aug 1999
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From: Gold Coast, Australia
Since this is a run-on landing to a runway and there is no implication of touching down with less than a positive airspeed and within U/C limits: what is the problem?
Unusual, certainly; but technically it sounds within limits and hardly something to be alarmed about. Out in the 'other' world of GA and aerial work you'll be coming in downwind, crosswind and vertically so there will be the usual plethora of Rotorhead views opined here, but this is my two pennyworth
Unusual, certainly; but technically it sounds within limits and hardly something to be alarmed about. Out in the 'other' world of GA and aerial work you'll be coming in downwind, crosswind and vertically so there will be the usual plethora of Rotorhead views opined here, but this is my two pennyworth
Joined: Sep 2008
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From: UK
tail wind approaches on helicopter
Mmmmmmmmm ???
1 If you know your downwind
2 If you keep checking you have enough Aft cyclic (to slow down)
3 You have checked the Power available and know you have enough. ( to stop the R o D )
YOU WON,T HAVE A PROBLEM.
The problems happen when the pilot either:
1 Doesn,t realise he,s downwind
2 Lets a High RoD develop
Mmmmmmmmm ???
1 If you know your downwind
2 If you keep checking you have enough Aft cyclic (to slow down)
3 You have checked the Power available and know you have enough. ( to stop the R o D )
YOU WON,T HAVE A PROBLEM.
The problems happen when the pilot either:
1 Doesn,t realise he,s downwind
2 Lets a High RoD develop
Avoid imitations
Joined: Nov 2000
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From: Wandering the FIR and cyberspace often at highly unsociable times
Some Class A performance profiles prohibit a tailwind.
Apart from that, I see no issues; in fact I sometimes need to carry out that type of approach.
Apart from that, I see no issues; in fact I sometimes need to carry out that type of approach.
Joined: Sep 2018
Aviation Qualifications: CPL
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From: California
,...and keep your feet awake, lol.
Hmm, just saw this thread is like twenty years old. Maybe have a statute of limitations on these things, 'cause,...dude!
Joined: Aug 2000
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H99 like all helicopter stuff it is all to do with energy ( power )management.
Show your student it takes more energy to hover downwind ( due to us not being able to hold a steady hover ). This then moves on to losing translational lift early and at some distance and height from LZ. Therefore more energy required !
So engine can only give so much energy, so we know we are going to use more energy to hover and last bit of approach. Add to this the amount of energy ( power ) required to slow the aircraft both horizontally and vertically . So easy answer to use less energy, ( so one has more energy to play with ) is to have a shallow approach ! Try a normal approach then turn it round ( ie same heights, distance and ground speed ) student will immediately slow helicopter down and have a larger rate of decent to get down, therefore building up a lot of energy in the airframe ! Does the engine have enough energy to arrest the rate of descent, student pulls lever up , result nose goes up slowing the rate of descent, or so he thinks , but at the risk of coming off of translational lift, more energy required, which will rapidly increase ROD, thrust is now not vertical it is is behind as student is flaring the helicopter, so more energy required, now tail wants to weather cock, so more energy required, still out of ground effect so more energy required, sloppy handing as shown in hovering downwind so more energy required and so on
Show your student it takes more energy to hover downwind ( due to us not being able to hold a steady hover ). This then moves on to losing translational lift early and at some distance and height from LZ. Therefore more energy required !
So engine can only give so much energy, so we know we are going to use more energy to hover and last bit of approach. Add to this the amount of energy ( power ) required to slow the aircraft both horizontally and vertically . So easy answer to use less energy, ( so one has more energy to play with ) is to have a shallow approach ! Try a normal approach then turn it round ( ie same heights, distance and ground speed ) student will immediately slow helicopter down and have a larger rate of decent to get down, therefore building up a lot of energy in the airframe ! Does the engine have enough energy to arrest the rate of descent, student pulls lever up , result nose goes up slowing the rate of descent, or so he thinks , but at the risk of coming off of translational lift, more energy required, which will rapidly increase ROD, thrust is now not vertical it is is behind as student is flaring the helicopter, so more energy required, now tail wants to weather cock, so more energy required, still out of ground effect so more energy required, sloppy handing as shown in hovering downwind so more energy required and so on
Joined: May 2002
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From: Downeast
For a look back into history re this topic of discussion.....we have been here before.
T/O Downwind -v- power available ?
T/O Downwind -v- power available ?
Avoid imitations
Joined: Nov 2000
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From: Wandering the FIR and cyberspace often at highly unsociable times
No longer my problem though. These days I keep myself busy doing all sorts of stuff rather than aviation.
Last edited by ShyTorque; 19th September 2023 at 19:43. Reason: Grammar.
Joined: Apr 2000
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From: EGDC
Is Cat A and Confined Areas a rather rare combination?
Robbiee - if you don't have HOGE performance, downwind approaches would be very unwise.
The rotor doesn't know it is downwind so any variations in power hovering downwind are to do with overcontrolling on the pedals.
For a safe downwind approach, fly shallower than normal, get the airspeed off early and maintain a sensibly slow groundspeed.
If you are too fast at the end, the temptation is to flare but you don't get any benefit from a change in RAF when you are already downwind.
If in doubt overshoot early.
Make sure you have at least HOGE performance before trying it.
Joined: Sep 2018
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From: California
Originally Posted by [email protected]
Robbiee - if you don't have HOGE performance, downwind approaches would be very unwise.
Joined: Mar 2019
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From: Europe
I don't teach CPL(H) but back when I was being taught, 'shallower than into wind' was certainly the theme. Various plausible explanations as to why, but I certainly feel more at peace flying a shallower approach if landing downwind.
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From: California
Joined: Oct 1999
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From: Den Haag
Joined: May 2002
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From: Downeast
Sure, when you're getting paid, shot at,...or rescuing a hot chick from a hoard of zombies.
Having no experience with hoards of zombies....and knowing you have to be around to spend money.....I cannot assign a probability of such things being an encouragement.
As to getting shot at....that will make you do a lot of things you would not ordinarily do.
Now as to the Blonde....if you are going to set a trap for helicopter pilots....that would be a good start.
Having no experience with hoards of zombies....and knowing you have to be around to spend money.....I cannot assign a probability of such things being an encouragement.
As to getting shot at....that will make you do a lot of things you would not ordinarily do.
Now as to the Blonde....if you are going to set a trap for helicopter pilots....that would be a good start.