Does wind affect OGE hover weight?
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Does wind affect OGE hover weight?
hello, everyone, I got a question about the OGE performance chart. To determine the OGE hover maximum weight, we draw the lines on the chart with OAT and pressure altitude. But I think the wind information is also a factor , say, if the helicopter can hover OGE at 4000ft with 5000lbs maximum gross weight under 0 wind condition, what if we got 10kts headwind, can we hover OGE at same level with more than 5000lbs gross weight? On the OGE performance chart, there's no wind information, so how can I get the weight under different wind direction and speed?
appreciate for your comments!
appreciate for your comments!
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123
The data you require (if available) will be contained in the approved Rotorcraft Flight Manual. The certification convention is that if forecast winds are used to predict performance then only 50% is accountable. If wind data is available from a certified anemometer at the operating site then a higher percentage may be used if permitted in your jurisdiction.
G.
G.
Makes a difference when winching marine pilots on/off large sea going vessels. A wind is a bonus plus any speed the ship can maintain for you.
Up to a point and then the deck turbulence gets annoying.
Up to a point and then the deck turbulence gets annoying.
Wind like airspeed is Your Friend
Obviously Wind greatly effects HOGE & HIGE 
Do NOT rely to heavily on the HIGE/HOGE graphs, they are to be used as a guide (only) 
how much does it effect??.........experience will only give You that answer, loads of experience of going out there, exploring & testing the envelope 
Happy Happy
Do NOT rely to heavily on the HIGE/HOGE graphs, they are to be used as a guide (only) how much does it effect??.........experience will only give You that answer, loads of experience of going out there, exploring & testing the envelope Happy Happy
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I was having a lovely time hovering OGE and admiring the view in a nice stiff breeze until I dropped below the demarcation line. I ended up exploring and testing a bit more than the envelope.
Live and learn; or is it learn and live? I can never remember.
Live and learn; or is it learn and live? I can never remember.
The hover OGE graphs are with zero wind. There is no requirement (under CS/FAR29 etc) to have graphs for OGE hover with wind effect, but flight manuals for some types may have it, typically in the non-approved part of the flight manual. Of course you could argue that hovering with wind is not really hovering. It is forward flight at a speed that happens to match the current headwind component!
JP's point is a serious one - if you are only able to hover due to the wind, what are you going to do when either the wind is less than expected, or it drops whilst you are hovering (maybe with nowhere to land)?
JP's point is a serious one - if you are only able to hover due to the wind, what are you going to do when either the wind is less than expected, or it drops whilst you are hovering (maybe with nowhere to land)?
Helicopter123 - the answer to your original question
is no, unless, as geoffers says, you have the graphs in your RFM specifying wind effect.
Does more wind give you free performance? Yes, unless you use that performance to exceed any other RFM limitations - Max AUM for example.
if the helicopter can hover OGE at 4000ft with 5000lbs maximum gross weight under 0 wind condition, what if we got 10kts headwind, can we hover OGE at same level with more than 5000lbs gross weight
Does more wind give you free performance? Yes, unless you use that performance to exceed any other RFM limitations - Max AUM for example.
We moved.
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Here are the numbers we use when training new pilots on the medium helicopters (B204,205,212).
In a OGE hover with a given torque you will get with wind up to:
10 Kts 250 lbs extra lifting ability
20 Kts 800 lbs extra lifting ability
30 Kts 1500 lbs extra lifting ability
Now what it means here is not to use these numbers to LIFT more, but to
be careful when windy condition prevails because you could overgross your aircraft without realizing it.
So yes, it does affect your OGE performances.
JD
In a OGE hover with a given torque you will get with wind up to:
10 Kts 250 lbs extra lifting ability
20 Kts 800 lbs extra lifting ability
30 Kts 1500 lbs extra lifting ability
Now what it means here is not to use these numbers to LIFT more, but to
be careful when windy condition prevails because you could overgross your aircraft without realizing it.
So yes, it does affect your OGE performances.
JD
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fijdor et al
There seems to be a worrying aspect creeping into this thread. People seem to be saying that you base your mass on what you can't away with. You are right - those that work like that can 'overgross', as you put it, unwittingly.
I beg you professional helicopter pilots to look at the mass situation for your flight BEFORE you get airborne. That's why the data is made available in the flight manual. It is I know unrealistic to have every kilo or every pound accounted for during certain types of operation but you should at least know how to regulate your mass according to the Density Altitude that relates to the working environment on that day, at that time of day.
Too many out there appear to believe the brochure when it says that because you have 10 seats (example) you can carry 10 passengers and three hours of fuel - don't forget the paragraph that says YES - BUT NOT AT THE SAME TIME.
G.
I beg you professional helicopter pilots to look at the mass situation for your flight BEFORE you get airborne. That's why the data is made available in the flight manual. It is I know unrealistic to have every kilo or every pound accounted for during certain types of operation but you should at least know how to regulate your mass according to the Density Altitude that relates to the working environment on that day, at that time of day.
Too many out there appear to believe the brochure when it says that because you have 10 seats (example) you can carry 10 passengers and three hours of fuel - don't forget the paragraph that says YES - BUT NOT AT THE SAME TIME.
G.
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Most helicopter pilots (but not all I admit) work using the limits, charts and whatever is available including experience to stay within the legal, safety limits of the aircraft and it is actually fairly easy to do AS LONG AS you know what's ahead of you, Like Geoffer said "to look at the mass situation for your flight BEFORE you get airborne" That's all nice but it is NOT always the case. Certain operations demands improvisations and guesses on what is ahead of you. Therefore sometimes on a windy day you may end up picking up a load that would have stayed on the ground the day before. Logging is a quick example of this, you never know what your next load is going to be even if they give you a "guesstimate" on the next log.
With a weigh scale on board or using known power settings etc a pilot should be able to figure out the weight he is picking up especially if he is experienced on the aircraft he is flying.
Also as a note here, wind will affect OGE hover weight and that can be either way Up or Down, the UP is the easy side of it.
JD
With a weigh scale on board or using known power settings etc a pilot should be able to figure out the weight he is picking up especially if he is experienced on the aircraft he is flying.
Also as a note here, wind will affect OGE hover weight and that can be either way Up or Down, the UP is the easy side of it.
JD
I can recall a few occasions in Northern Ireland back in the day when aircraft were inadvertently overstressed by a combination of weighing errors (describing the load weight in pounds when it should have been kilograms) and pilots being lulled into a false sense of security when lifting loads from hilltops in windy conditions.
Once you get away from the wind it all becomes a bit embarrassing if you haven't got your sums right!
There does seem to be an attitude that 'overgrossing' is an acceptable way of doing business but your aircraft is designed and certified to a certain set of conditions and limits (the RFM graphs) and ANY exceedance of those limits erodes the safety margin for both the short and long term integrity of the aircraft, whether that be engines, rotors, transmission or the structure of the airframe itself.
One of the first things any accident investigator would look at would be the weight and balance of the aircraft to see that it was being operated within the limits of the RFM - if it is outside, that has lots of legal implications, not least insurance invalidation.
Once you get away from the wind it all becomes a bit embarrassing if you haven't got your sums right!
There does seem to be an attitude that 'overgrossing' is an acceptable way of doing business but your aircraft is designed and certified to a certain set of conditions and limits (the RFM graphs) and ANY exceedance of those limits erodes the safety margin for both the short and long term integrity of the aircraft, whether that be engines, rotors, transmission or the structure of the airframe itself.
One of the first things any accident investigator would look at would be the weight and balance of the aircraft to see that it was being operated within the limits of the RFM - if it is outside, that has lots of legal implications, not least insurance invalidation.
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Wind Benefit
Wind benefit is not calculated by halving the wind intensity. Wind benefit is the actual weight increase produced by the presence of the wind, therefore any discount is the weight discount and not the wind.
Wind benefit is mandatory factored to 50% only for Cat A certification, for all the other performance data, including the mandatory performance, data can be presented unfactored, i.e. with 100% benefit. It is upon operator responsibility to use the correct factorized weight based on the operational rules where he is operating.
Wind benefit is mandatory factored to 50% only for Cat A certification, for all the other performance data, including the mandatory performance, data can be presented unfactored, i.e. with 100% benefit. It is upon operator responsibility to use the correct factorized weight based on the operational rules where he is operating.
