Go Helicopter Vacation - San Francisco

Go Helicopter Vacation - Big Bear

    I am still working on this part of the web site.  Because it has turned into a hobby, I have limited time to work on it.  I am about to take this machine on a vacation trip with my family.  We intend to go from Orange County to the San Francisco area for five or six days of seeing the sites and visiting friends.  We plan to take lots of pictures.  I will put a link on this page and share them with any who might enjoy them.  I look forward to the trip.
    I have always enjoyed helicopters.  I did not fly them much for about 15 years, and only recently got current in order to provide some instruction for two of my friends that each own a Gazelle.  It's a shame they don't still make these helicopters, because they are better than the Astar that replaced them.  They leave other helicopters, and many light airplanes in the dust.  A cruise speed of 130 knots is quite realistic.  It feels great when ATC asks you to slow down to follow an airplane in the pattern.  That happens often in the Gulfstream, but is kind of special when you are flying a helicopter.
 
 

"Gazelle"

SA-341G

 
Gazelle Landing

 
 
 
On The Ramp



Performance / Weight & Balance

Maximum Airspeed vs Altitude

Altitude
SL
2000
4000
6000
8000
10,000
12,000
14,000
16,000
18,000
20,000
Vne / KTS
168
160
152
144
136
128
120
112
104
96
88

    Center of gravity is of prime importance.  Out of CG will kill you much quicker than over weight.  Operating outside the CG limits in a helicopter will more than likely result in a crash shortly after lift off.  A great way to increase your chances of survival is to operate within the limits in the table below.  Do we solve a weight and balance problem before each and every flight?  No, not unless we are operating on an air carrier certificate.  Compute weight and CG for the typical loading you plan to use.  If you are going to deviate from your typical loading profile, work a problem to see if you are still within limits.  When leaving the ground with an unfamiliar loading configuration, Always transition to a hover slowly, and note where the cyclic must be positioned.  If more than one half deflection in any direction is required to maintain your position and attitude, set down and adjust the load such that less than half control deflection is required.  This will result in a longer life for both you and the helicopter.
 

CG vs Datum
Left
Right
Forward
Aft
Inches
6.0 Inches
5.3 Inches
110.2 Inches
123.6 Inches
Meters
0.152 M
0.135 M
2.8 M
3.14 M

Datum = 118.1 inches or 3 Meters forward of center of main rotor head.


 
Pounds
Kilograms
Maximum Gross Weight
3,970 lb
1,800 KG

Note:  Maximum gross weight may be limited by the helicopters ability to hover.
           See Page 6 in section 4 of the AFM.  The data computed from this chart
           is an Operating Limitation for the Gazelle Helicopter. Comply with it.

    For the Gazelle, as well as other helicopters, there are two charts that address the particular helicopters ability to hover.  They are IGE, or "In ground effect", and OGE or "Out of ground effect.  In the case of the Gazelle, the IGE chart is limiting.  If you comply with the limits in this chart, you are legal, and more than likely safe to operate as long as the takeoff and landing areas are free of obstructions in your proposed takeoff or landing flight path.  The "OGE" or out of ground effect hover ceiling chart is the one to use when operating in a confined takeoff or landing area, or when faced with obstructions in your proposed flight path.  For example, landing on a roof top helipad would be much safer if you comply with the "OGE" hover chart, because you would not need to remain in translational lift until hovering over the pad.  If you can hover out of ground effect, and limit your rate of descent to 400 fpm or less, landings on rooftop helipads, or aboard a yacht may be done quite safely.

Maximum Weight / Hovering In Ground Effect.

Temp / Alt
-20C
-10C
0C
+10C
+15C
+20C
+25C
+30C
+35C
+40C
+45C
SL
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
1,000 ft
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
2,000 ft
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,830
3,700
3,000 ft
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,890
3,710
-----
4,000 ft
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,900
3,720
-----
-----
5,000 ft
3,970
3,970
3,970
3,970
3,970
3,970
3,880
3,740
3,600
-----
-----
6,000 ft
3,970
3,970
3,970
3,970
3,970
3,910
3,730
3,620
-----
-----
-----
7,000 ft
3,970
3,970
3,970
3,950
3,860
3,720
3,610
-----
-----
-----
-----
8,000 ft
3,970
3,970
3,940
3,790
3,720
3,630
3,490
-----
-----
-----
-----
 9,000 ft
3,970
3,910
3,820
3,640
3,560
3,490
-----
-----
-----
-----
-----
10,000 ft
3,970
3,780
3,680
3,540
3,480
3,380
-----
-----
-----
-----
-----

Maximum Weight / Hovering Out Of Ground Effect.

Temp / Alt
-20C
-10C
0C
+10C
+15C
+20C
+25C
+30C
+35C
+40C
+45C
SL
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,800
3,600
1,000 ft
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,840
3,800
3,500
2,000 ft
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,970
3,700
3,560
-----
3,000 ft
3,970
3,970
3,970
3,970
3,970
3,970
3,890
3,740
3,600
3,400
-----
4,000 ft
3,970
3,970
3,970
3,970
3,920
3,860
3,750
3,640
3,480
-----
-----
5,000 ft
3,970
3,970
3,970
3,850
3,750
3,710
3,610
3,500
3,380
-----
-----
6,000 ft
3,970
3,970
3,850
3,700
3,650
3,610
3,500
3,390
-----
-----
-----
7,000 ft
3,970
3,820
3,700
3,600
3,480
3,460
-----
-----
-----
-----
-----
8,000 ft
3,870
3,700
3,600
3,480
3,390
3,350
-----
-----
-----
-----
-----
 9,000 ft
3,700
3,550
3,420
3,300
3,240
3,300
-----
-----
-----
-----
-----
10,000 ft
3,610
3,450
3,240
3,210
3,130
-----
-----
-----
-----
-----
-----

Maximum Torque

Alt / Temp
-50C
-40C
-30C
-20C
-10C
0C
+10C
+20C
+30C
+40C
+45C
SL
100%
100%
100%
100%
100%
100%
100%
100%
100%
90%
85%
3,000
100%
100%
100%
100%
100%
100%
100%
98%
90%
80%
------ 
6,000
100%
100%
100%
100%
100%
100%
94%
87%
80%
------ 
------ 
9,000
100%
100%
100%
100%
95%
90%
84%
77%
 ------ 
 ------ 
 ------ 
12,000
100%
98%
94%
90%
85%
80%
75%
 ------ 
------ 
 ------ 
 ------ 
15,000
92%
88%
84%
80%
76%
71%
 ------ 
 ------ 
 ------ 
 ------ 
 ------ 
18,000
81%
77%
74%
71%
67%
 ------ 
  ------ 
 ------ 
 ------ 
 ------ 
 ------ 
20,000
74%
71%
68%
65%
 ------ 
------ 
 ------ 
------ 
 ------ 
 ------ 
 ------ 

 
 
Engine / Fuel / Hydraulics

Turbomeca Astazu III A Engine

 
Maximum
Minimum
Engine Power
592 HP / 440 KW
-----------
Engine RPM
43,500 RPM to 43,900 RPM
+/- 1,500 / rapid collective
Transmission Power Limit
494 HP / 368 KW
-----------
EGT
550 deg C
-----------
Oil Pressure
72.6 psi
21.7 psi to 11.6 psi
Oil Temperature
+85 deg C
+5 deg C
+30 deg C when OAT
less than + 5 deg C

    The hydraulic system on the Gazelle provides hydraulic boost for the Cyclic.  The hydraulic pump is driven by the transmission, not the engine.  This allows it to function during autorotation in the event of engine failure.  The aircraft is controllable without the hydraulic boost, but the control forces are higher.  The boost can be turned on and off with the switch located on the left collective.


    The fuel tank system on the Gazelle consists of one main tank.  This tank holds up to 120.2 Gallons.  An optional Aux Fuel Tank is installed on some aircraft.  It has  a fuel capacity of 24 Gallons, and fills itself automatically when the main fuel tank quantity is 30 gallons or greater.  As fuel is added the main tank will remain at 30 gallons until the Aux is full, then increase as fuel is added until both tanks are full.
 

 
Jet / Diesel
Gasoline
Maximum Altitude
20,000 ft
6,500 ft
Note:   Below +5C Fuel anti-ice additive required


Operational Limitations & Procedures
 Ambient Temperature
-50 deg C to +45 deg C 
 Slope Landing
(Avoid with less than 13 Gal Fuel)
9 deg Side 
12 deg / Nose Uphill
 Moving Platform
 35 kts Relative Wind
30 kts 30 deg +/- Centerline
9 deg Roll / 2 deg Pitch
 Clutch Engagement
Twice in 5 Minutes 
 Min Visibility in Snow
2,500 ft
Inspect for Ice each hour
 Max Vertical Descent
400 ft / min 
 Max Wind to Start
or Stop Main Rotor
40 kts
Over 25 Knots / Full Rotor
Brake from 170 RPM to Stop
Best Rate of Climb / SL to 10,000 ft
65 kts
Best Rate of Climb above 10,000 ft
55 kts

Rotor RPM Limitations

 
Minimum
Low RPM Warning
Maximum
Powered Flight
366 RPM
360 RPM
390 RPM
Autorotation
310 RPM
360 RPM
430 RPM
Autorotation @ -15 deg C
310 RPM
360 RPM
415 RPM
Autorotation @ -30 deg C
310 RPM
360 RPM
410 RPM

Note:    Add 10 RPM to minimum rotor RPM for each 3,300 feet above 3,300 MSL

Autorotation from 10,000 ft @ 65 kts = 3.25 nm distance
 
 


Back to: Study Guides Page
 

Back to: Airplane Driver's Network