Single-engine Piston Aeroplane (SEP)	4

Answers to Climb Examples

1.

Time	Fuel	Distance
13	4.8	27
33 NGM

2.

	Time	Fuel	Distance
FL120	14	5	29
3000 ft	3	1	5
Difference	11	4	24
17 NGM

Cruise Power Settings Tables

Each table in the Figure 2.2 series shows the performance data for a given power setting. For example, table 2.2.1 is for:

Manifold pressure of 25.0 inHg (mercury) @ 2500 rpm.

The data is given for three different ISA temperature deviations: STANDARD DAY, ISA +20°C and ISA -20°C. Note that above a certain altitude (full throttle height ), the stated manifold pressure cannot be produced by the engine and the tabulated values of manifold pressures (shaded areas) are approximately the maximum that can be expected.

The tables are used by turning to the page for the selected power setting and then selecting the appropriate Pressure Altitude and interpolating for each single degree of ISA Deviation to extract the necessary information.

Interpolation between pressure altitudes is required.

Cruise Example

3.Refer to CAP 697 Figure 2.2 & 2.3 and extract the following data

TAS IAS PPH USG

Given: 25” @ 2500 rpm	FL90	ISA +5°C
Given: 21” @ 2100 rpm	FL90	ISA -15°C
Given: 23” @ 2300 rpm	FL100	ISA +10°C

Single-engine Piston Aeroplane (SEP) 4

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(SEP) Aeroplane Piston engine-Single 4

4	Single-engine Piston Aeroplane (SEP)

Answers to Cruise Example

3.Refer to CAP 697 Figure 2.2 & 2.3 and find the following data

			TAS	IAS	PPH	USG
Given: 25” @ 2500 rpm	FL90	ISA +5°C	167	147	75.55	12.6
Given: 21” @ 2100 rpm	FL90	ISA -15°C	142	130.5	59.1	9.77
Given: 23” @ 2300 rpm	FL100	ISA +10°C	157	134	65.10	10.85
ISA	ISA +20
157	156
137	132
66.2	64
11	10.7

Range Profile Figure

This table gives an estimate of the maximum still air range, for each of four power settings, for a selected pressure altitude.

The calculated range includes fuel for:

•Climb

•Cruise

•Taxi and run-up, plus

•A reserve fuel for 45 minutes at economy cruise power

This table enables the pilot to rapidly select a suitable cruise level for a route distance and preferred power setting. It is also possible to select a power setting, given a preferred cruise altitude and route distance.

To use the table, enter on the left with cruising pressure altitude and move horizontally to the selected power setting curve. Move vertically downwards to read off the range in Nautical Air Miles.

You will note that on each power setting curve that TAS is quoted for Pressure Altitudes 4000 ft, 8000 ft and 12 000 ft. You may have to interpolate between these altitudes to extract an accurate TAS to use in the conversion of NAM to NGM.

Note. Range is affected by wind, therefore you will have to convert the NAM extracted from the graph into NGM, using the formula discussed in Chapter 3.

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Single-engine Piston Aeroplane (SEP)		4

Range Examples

4.	Refer to CAP 697 Figure 2.4	Extract Range (NAM)
	Given: Full Throttle @ 2500 rpm	FL100
	Given: Full Throttle @ 2100 rpm	FL100
	Given: Full Throttle @ 2300 rpm	FL70

5.Given:

Full Throttle @ 2500 rpm FL80 30 kt tailwind component What is the ground range?

Answers to Range Examples

4.	Refer to CAP 697 Figure 2.4		Extract Range (NAM)
	Given: Full Throttle @ 2500 rpm	FL100	839
	Given: Full Throttle @ 2100 rpm	FL100	904
	Given: Full Throttle @ 2300 rpm	FL70	832

Single-engine Piston Aeroplane (SEP) 4

5.Given:

Full Throttle @ 2500 rpm FL80 30 kt tailwind component

What is the ground range ?

799 NAM from graph, also extract a TAS of 169 kt from the graph

TAS	=	NAM	169	=	799	x = 941 NGM
GS		NGM	199		x

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(SEP) Aeroplane Piston engine-Single 4

4 Single-engine Piston Aeroplane (SEP)

Endurance

The table gives endurance (how long the aircraft can remain airborne; not necessarily the time to achieve the maximum range). Use in a similar manner to Figure 2.4.

As this endurance includes a 45 minute reserve the endurance you extract is called a safe endurance.

Note. Endurance is NOT affected by wind.

Endurance Example

5.	Refer to CAP 697 Figure 2.5	Extract Endurance
	Given: FT @ 2500 rpm	FL100
	Given: FT @ 2100 rpm	FL100
	Given: FT or 23” @ 2300 rpm	FL70

Answer to Endurance Example

5.	Refer to CAP 697 Figure 2.5		Extract Endurance
	Given: FT @ 2500 rpm	FL100	5.1 hrs	5 hrs 6 min
	Given: FT @ 2100 rpm	FL100	6.35 hrs 6 hrs 21 min
	Given: FT or 23” @ 2300 rpm	FL70	5.2 hrs	5 hrs 12 min

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Airfield “A” Data	Elevation	MSL	Aircraft plans to cruise to “D” at 23” 2300 rpm power
	Temp	+20°C	Using SEP Fig 2.1 and Fig 2.2 complete the fuel log
Departure Mass		3400 lb	Calculate the Trip Fuel, Time En route and ETA at “D”

Aircraft takes off from “A” at 10:00

and climbs from “A” to FL80 (temperature at TOC is 0°C) Wind Light & Variable

FROM

TO

FL

ISA

W/V

TAS

NGM

TK

HDG

GS

TIME

FUEL

FUEL

ETA

DEV

FLOW

REQD

A

TOC

L & V

120

100

TOC

B

80

+5°C

230/30

120

B

C

100

0

270/40

150

160

C

D

60

-10°C

200/20

80

130

TOTALS

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1 Exercise SEP

4 Questions

Questions 4