ROT Flashcards
Memorization
If I land at Vapp +10% what happens to my actual landing distance used (i.e. 6kts fast)?
Actual Landing distance increases by 21%
If Mtow is increased 10% (200lbs) what affect does this have on my required takeoff distance?
Takeoff run will be 21% longer…
Don’t fly in Mountains with >XX__kts wind at my current level or YY_kts wind at the Peak tops.
X= 15kts; Y= 20kts
Anytime within 1/2 sm (2000’ horizontally) from a ridge line, at what Lateral angle should I be tracking?
45 deg or less, never approach perpendicular…
Valley breeze will be ____ in the morning
Uphill, due to Sun’s initial heating at lower levels
I should always land up or down stream?
Upstream (uphill)
Late afternoons the valley air will be moving which direction?
Down valley, as cooling air is heavy and descends…giving a tailwind on takeoff in many cases…on 1-way airfields.
50/70 (@%Tora / %Vr) ROT vs. 30/70?
If there is a 50’ obstacle to clear…we use 30% of Tora to have reached 50% of Vr
Should you ever fly in the middle of a Canyon?
NO
Does stall ias remain same at all altitudes (assuming same G-loading)?
Yes
What is my Mountain Flying Wx minima?
12km or 6nm, Ceiling >3000’+
All visible peaks clear of Cloud
Wind <20kts at Peak level
Once airborne Mountain Flying Wx minima
8km or 4sm or 5000’agl ceiling…
Winds must be <22kts
If worse then Land!
How much extra TORA is required to overcome 1/8 inch of Frost on wings?
50% more Tora
Wait for Sun to melt it
Should you use the same Vref while operating in Mountains?
Yes, it is self-correcting with different heights…
How much does Tas > with every 1000’
2%
What should I do differently if parked on a slope?
Turn Fuel selector off?, select the lowest wing to avoid syphoning of fuel from higher wing towards the lower wing, then out my vent.
Is it better to shuttle climb or descent in Mountainous terrain?
Both…it’s not about going ‘Direct’
What precaution should you take prior to entering an upslope valley…
Gain altitude ‘prior’ to entering it!
At what Density Alt should you start to lean your mixture for Takeoff?
3000’
Plan to Land at least XX minutes before sunset in Mountainous terrain
60min
Due to possible diversions, time for Shuttle climbs and long Shadows late in the day.
Rule #1 in Mountain Flying…
Always remain in a position to turn towards lower ground.
Turn back assumptions in Mountains…
Turn will be started at 500’agl, it will be steep with 50deg aob turn, assumes Idle Power (to cater for any downdrafts or EO glide); but not flown that way!
Just put V-Bar on imaginary horizon
What’s the absolute lowest alitude I should fly in rising terrain?
500’agl
What is the most unique mindset used for 180deg turn back in Mountains?
The Assumption it will be done from 500’ agl and at idle power ‘in my minds eye’, but actually done at Max power in realtime (safety margin!)
Could use mechanical and/or convective lift improve my climb…but always turn…
Away from the mountain in figure 8, never towards it…45 deg towards and turn 180deg away…so end up 45 towards it.
SAR distance rules from lateral & Vertical walls of a Canyon?
500’ from both, caters for downdrafts and turbulence.
How many G’s of lateral decelleration can body absorb?
40g
How many G’s of vertical Decell can body endure (i.e compression on spine/neck)?
9g, so never stall it in tops of the trees…
When going down…fly at 1.3 Vs and flare Land it…
Uphill, anytime force land, ditching…never stall or decrease speed below 1.3 Vs
For Tree’s, don’t even flare
When I realize that I will need to force land on an ‘Uphill slope’ what speed should I fly?
1.4 Vs because you’ll need much more flare
With a clean wing, never fly less than XX kts in the Mountains (or anywhere else)
80kts
What is trade-off with Flaps out?
Slower ias, tighter radius, but lower Ultimate load factor of 2.2G
At what power setting should you do a Canyon Turn (turnback)?
Max Power
Main reasons not to fly closer than 500’ from a canyon wall?
Snags (i.e. single big grey dead trees, unseen Power lines)
Severe Turbulence
What often ‘lures’ you closer than 500’ from a canyon wall?
Lift
How is a ‘Narrow’ canyon defined?
Anytime turnback would use more than 1/2 the width of a canyon
~ <4000’ wide
What is MAJOR difference when it comes time to choose the side I would fly up a “Narrow” canyon?
You must fly up it on the ‘Downdraft’ side; so your turnback is with updraft…logical…
45deg aob at 80kts Tas…diameter
45 deg aob at 90kts Tas
1150’
1500’ diameter (need 2000’ with 250’ buffer on each side or 600m)
Higher you are, the more Tas for same 80kts ias, hence, the larger your?
Turn diameter, path over-ground to turn around
At 5000’ msl your turn diameter is what percentage larger?
Your speed is 10% more, but diameter is 20% more b/c speed effect is squared in turn radius equation…
…So a small canyon becomes anything less than 1sm wide!
What shift in winds is expected in 90% of takeoffs?
They will increase and shift Clockwise (veering or veers)
From altitude to the ground I can expect winds will ?
Back and decrease
(Less # on compass; i.e. smaller number on compass scale)
Can you enter a ‘rising’ terrain canyon if there is insufficient room to turn around?
No
If you double your ias from 80kts to 160kts, what happens to my turn Radius?
It Quadruples…velocity is squared in Kinetic energy equation
What is kinetic energy equation?
Kinetic energy is directly proportional to the mass of the object and to the square of its velocity:
KE = 1/2 m v2
If the mass has units of kilograms and the velocity of meters per second
Why are flaps ultimate load only 2.2g vs. aircraft 3.8g?
Flaps have no spar; once they rip off, your now assymetric and going down…be cautions.
Best rate of climb Vy found at what Pitch attitude?
~ +7deg Nose-up
Liftoff usually below Vy and witih PA of 4 to 8deg or so
How to figure out DA on my iphone…
E6B app= Altitude, Density Alt.
-Elevation
-Alt. Setting
-Temp in Deg C
-Dew point in Deg C
With a Constant Speed Prop, for takeoff >8000’ DA what % should be added to TORA for each +1000’?
15%
You add +10% for each 1k below 8000’
With CSP Reduce ROC by xx % for each +1000’ DA; once above 8000’ DA reduce by yy % for each added 1000’ of DA
xx: 6%
yy: 8%
Takeoff distance varies with Square of what?
My Takeoff Weight
Note…30% more weight when squared gives 1.69 or 70% longer Tora!!
+Must also mega-adjust for any ‘obstacles’ at departure end of Runway
(i.e. how high are those trees)
[BH solo empty 1550lbs to 2350lbs weight range, 40% spectrum]
[I am assuming 1800lbs is 100%]
{Max Gross is 30% more weight @2350lbs= 50% longer Tora than Dirk solo full tank, no bags}
[~Min weight for takeoff ever would be 10% less weight than 1800lbs]
True/False High Density altitudes on the day combined with Heavy weight corrections can Quadruple my Sea-level Solo takeoff distance?
True
Does using same ‘ias’ for Vr and Vref compensate for high DA?
Yes, pitot tube is receiving same number of molecules!
And you’ll actually be at the required Higher TAS…
A ten percent increase in TOW (200lbs) or 1-pax causes?
5% increase in T/O Speed
9% decrease in Acceleration
21% increase T/O Distance
*Offloading your pax has the opposite effects (good)
Headwind will reduce normal takeoff distance using what ratio?
As a starting point probablhy 90% of Tora required because of headwind
Then ‘subtract’ the ratio of…
Headwind / Rotation speed
as a Percentage…for instance…
6kts head/50kts Vr = so Subtract 12% (hence, normal Tora distance * .88)
so, 700’ tora becomes 554’ in nice 6kts headwind
Influence of winds…on takeoff
Example 2kts head?
Example 20kts head?
90% Tora - 2/60kts= 3.3% so 87% of Tora
90% Tora - 20/60kts= 33% so 57% of Tora
How much does 10kts headwind component reduce today’s Tora?
25% or so (wag)
How much does a tailwind that is ten percent (6kts) of Vr thereby increase my Tora?
21% more Tora needed (much larger affect on Tora with tailwinds than headwinds)
Formula for tailwind effect on Tora?
Tora * 110% + ratio Tailwind component/Vr in percentage
Example=
700 tora * 1.1= 770’ + 5tail/50 10% 1.1 (which is another 77’)= 850’
Or just use 70/50 if no obstacles
Max Tailwind I would accept is 4kts…used in Tora formula
110% +
4/60= 6.7%
Tora becomes 117% of usual distance
or use 70/50 rule…
At 5 kts tail becomes a directional control issue!
How much distance does a C-170 at 5000 DA and 10kts tailwind need to takeoff?
1900’ Tora assuming ‘no’ obstacles on departure
(i.e. a lot!)
What modification to normal takeoff should be done in Gusty conditions?
Keep aircraft on ground until Vr + 1/2 Gust factor, which will be +5kts.
(i.e. Lift the tail more)
I don’t takeoff in gusts >11kts
ROT to apply for these surfaces:
Firm Turf
Rough, Rocky, Short Grass
Long Grass (>4 inch)
Softfield & Sand
Mud or Snow
+7% Firm Turf
+10% Rough, Rocky, Grass
+25% Long Grass (>4 inch)
+25%-75% Softfield & Sand…
+50% Mud or Snow
*Note wet grass would combined % of Softfield + Grass i.e. 35%
*Alternatively 50/70 rule works well…
One-percent downslope is equivalent to xx % more Ldr?
5%
Each 1% upslope will increase Tora needed by?
10%
But, once I hit 6% upslope…my limit…Tora increased by only 40%
(Not sure why…)
What is maximum slope I shoud normally consider using?
5 deg up or down slope, gradient 8.75%
Goes up 23” over length of my a/c…
6-9deg is extremely difficult!
Never more than 9deg…which is up 1’ for every 6’ forward, which is more than height of my tires over length of my aircraft!
% slope is that 90deg is equal to 100%
(Tan angle slope) x100: Gradient
Why consider Dew point in Performance Calculations?
Because more Humid air is ‘less’ Dense!
True/False Older engines (more hours) won’t perform as well?
True
Certain local terrain shapes cause downdrafts after takeoff…
These effects can exceed climb capabilities of my a/c.
Think of what water would do, if this terrain was a river?
Pireps and Field guides give guidance on local conditions, mind-those…
Whats the difference in drag reduction by flying at 2’ vs. 15’ after takeoff?
Up to 4x less drag flying at 2’ as that eliminates 60% of induced drag!
Probably gain equivalent of 4-5kts Performance or 10%
Common visual illusion that causes Vr error at high DA airports?
You feel like your going plenty fast enough (you are in Tas terms) but your NOT in IAS terms, trust airspeed indicator for proper Vr, don’t rotate early or pull it off the ground, wait until if flies off at usual Climb attitude for every other Takeoff…be patient…
So…Spring my Flaps later than usual!
Always the most Induced drag when?
At Vr or in flare
And above 35’ agl when ground effect vanishes and your at your highest aoa and slowest ias, generating most lift you can
True/False it is a good idea to learn to fly at 2’ in calm air and 3’ otherwise..
True, to Maximize Ground Effect after takeoff until Vy, every foot counts, but don’t ‘Skip’ off the surface either!
Accel to Vx while retracting flaps in ground effect then leave Ground effect in Clean Config after achieving Vx to clear obstacles (50’ trees)
On takeoff I cannot set a dangerous Pitch attitude, as my a/c is not stalled in 3-point attitude, but…
Once airborne, or in Map I could over-rotate my Pitch Attitude and Aoa.
What happens if you wait for liftoff with only a 3deg Nose up PA?
Longer Tora but take off closer to Vy and not need ground effect and be safer in Turbulence or Gusts
Better to Set a 0 deg Aoa until Vr +Gust factor instead of just setting 3 deg PA..
What should you do when your line-up for takeoff?
Look for a prominent landmark or cloud ‘beyond’ the end of the Runway, for directional control with tail-down…
2700 rpm, Eng Green, 40 kts, Flaps
When should you smoothly lift the tail on takeoff?
Once you have proper Elevator Authority resulting from aerodynamic forces.
Occurs early with Propwash
Sop takeoff would be Tail low (assuming no Gusts); it’s off the ground though!
True/False Can consider snatching 1 notch flap once tail is up while looking straight forward?
True, be patient, past 40 kts
Why must you avoid a 2nd touchdown after your airborne in Ground effect?
Damage aircraft with Sideloads!
Structure is not designed to make much side-loading at all.
True/False, you always re-trim as you exceed Vx and transition to Vy climb
True
Fine tuning trim I set on takeoff
True/False viewed from cockpit the propeller rotates Counter-clockwise?
False
It rotates Clockwise
Three advantages to Snatching out flaps after Tail is up?
- Less drag during initial accelleration
- Less chance of damaging flaps with Flying debris from my Propwash
- Rudder effective at slower ias as Propwash flows back uninterrupted
Should I lock brakes as I put full power for a Short-field Takeoff?
NO, it will tip-over…prop strike
What can result from using full power while stationary?
Prop will pickup rocks and/or debris that will damage the Prop.
Tipping over Prop Strike
Never set over 1800Rpm on ground
Whats the ROT for Vapp adjustements vs. Weight reduction?
% we Reduce Vref is 1/2 of % of weight reduction
i.e. 10% less is 5% lower Vref
<200lbs is 2.5kts slower
Total Vref range is 1600-2350 (40% weight change) or 20% speed change which is 10kts, so slowest Vref to fastest Vref at Mtow is a range of 10kts.
Vref 50 to 60 kts
How to correct for a small Balloon during flare?
-Check forward to level flight
~Add some power, a small amount
-Re-establish 3-point attitude
If landing is long, just Go-Around!
In Mountainous Terrain, as natural horizon is often not visible, what’s the baseline for Level flight?
Assume horizon is at the Base of Mountains approximately 7 miles ahead.
What is Pitch Attitude for best ‘rate’ of Climb?
Horizon just below Cowling but visibly intersects both sides of the cowling at Vy of 75kts.
Vx is feet on Horizon?
Practice transitioning visually between Level flight and both Climb attitudes, should end up within 1 kt of Vx 64 kts or Vy 75 after takeoff at my local airport.
What attitude change occurs in the flare?
From my spot aimpoint to my taxiing pitch attitude on ground.
…Slowly…to not balloon
…Small burst power to cushion Ldg
What procedure could be used in extremis for strong crosswinds at Destination?
Divert
Land on into wind Taxiway
Land Flaps 3, assuming landing distance permits…
Which landing provides a shorter landing when proficient?
3-point, Stick Back
Retract Flaps down to F1
Brake without letting tail rise!
*Maintain directional control!
What happens when a figure skater extends arms while spinning?
She slows down the spin, as that reduce the moment of her inertia!
But we cannot ever do that…
What do you need to reduce the swerve in extremis above >28kts?
Add Power to Go-Around
Realize, if swerved beyond a certain angle…it’s not recoverable, don’t add power.
Flight Planning rule for each 1000’ of cruise altitude?
Add 1 min to enroute time (due to slower climb speed )
Celcius to Farenheit?
Double it & add 30
x2 +30
Effect of higher than usual humidity on Tora?
Add 10%
A two-percent change in weight causes a __ % change in Stall speed?
1%
40% means 20% more or +8kts stall
10% increase in Mtow causes?
5% more speed need to liftoff
10% slower accelleration rate
20% longer Tora
but 50/70 is still valid…dist/speed
‘45’ verbalize prior to Halfway point
True of False? Takeoff Distance varies with the square of the weight change?
True
20% more weight is 44% more Tora
1.2 * 1.2= 1.44
30% more weight is 70% more Tora
[So my worst Tora can be double my best Tora on same runway]
With an obstacle & @Mtow requires 4 times my lightweight airborne distance of 400’ x4= 1600’
If your 20% lighter then how much less Vapp you can expect?
10% lower Vapp or 5kts
Vapp reduced by half of % decrease in overall weight.
Will you be able to make a high speed descent if winds change by six knots per 1000’ ?
No
It will be bumpy
Carb Heat On
Plan a -100fpm, 80kts, set 16mp that is just above idle
Sea level Tora at Mtow 2350lbs
About 800’ no obstacles
Sea level Mtow Tora over 50’ Obstacle
1600’
Sea level ROC and Ias…
800’fpm, 75kts Vy
Max 3min or 2500’agl or so
Formula for Tailwind increase Tora?
110% times normal distance
Plus % of ratio: tailwind speed/rotation speed
‘45’ by halfway point of Tora
Upslope Takeoff ROT?
add 10% on Tora per deg of upslope
“45” halfway,no obstacles still works
Downslope Takeoff ROT?
Decrease Tora by 5% per deg slope down
How long should you fly in Ground effect?
Until clean and >64kts (i.e. Vx)
Should know what OPT parameters for BH?
Tora, Land distance, ROC and Sea level and every 2000’ increment until 10000’msl
For a Constant speed prop, above 8000’ DA what correction apply to Tora for each additional 1000’ da
+15% for each 1000’ above 8k
Reduce Sea-level ROC by __ amount per 1000’ altitude gain when below 8000’
6%
but…
8% when above 8500’msl
Should know my aircraft ROC at 2350lbs and 1800lbs
Log it at various MSL alt 2-4-6-8-10k
Helps me plan my escape from a Downdraft!
If losing directional control between 13-27 kts you should?
Use assymetric brake on outside
Ailerons to keep wings level
If losing directional control at less than 12kts…
Brake to outside
Stick back and to outside of turn, for added drag
